Analysis of infinite-draw decks

This is going to be a long post. Here's a list of the topics I intend to cover:

• What is an infinite-draw deck?
• Why is infinite-draw bad for the game?
• What makes infinite-draw possible?
• What can be done to prevent infinite-draw?

The key point of this post will be a set of item design guidelines for Blue Manchu which will make infinite-draw decks impossible without changing any of the existing game rules. This will be in the final section. (ie. 'what can be done')

What is an infinite-draw deck?
An infinite-draw deck is a set of cards which allows the player to play an unlimited number of cards in one round by continuously drawing new cards from their deck. With such a deck, the player will typically be able to have all 36 cards from one of their characters in their hand at one time. With an infinite-draw deck, once the player draws the right cards to begin their infinite draw combo they will be able to continue playing and drawing new cards indefinitely, regardless of any unlucky draws.

Why is infinite-draw bad for the game?
In single-player games, infinite draw is not really a problem. But in multiplayer it is a big deal. If a player is ever able to start an infinite-draw combo in a multiplayer game, their opponent won't be able to do anything at all. The infinite-draw player will just continue to play out their combo, for however much time it takes, while the other player will have no choice but to continue pressing 'pass' until the game is over. As long as the infinite-draw player has at least 1 card that can damage the enemy, and at least one card to move their own character, then they will win the game eventually. This is bad for balance in that the infinite-draw combo is undefeatable once it gets started - even if the combo is difficult to get started, the fact that it can be done and that it will always win the game is enough for it to be considered imbalanced in the extreme. And it is certainly bad for gameplay, because it will result in one player doing absolutely nothing while the other player just plays cards in a systematic and repetitive way to continue their combo and win the game. So I believe it is vital that the game is designed in such a way that infinite-draw is impossible, for balance and for fun.

What makes infinite-draw possible?
Infinite-draw is made possible by cards which allow the player to immediately draw additional cards, so that they can increase the total number of cards in their hand. This includes cards such as Inspirational Thinking, Inspiring Presence, Unholy Power, and Demonic Feedback. For example, if you imagine a deck which has nothing but Inspiring Presence in it, it's easy to see how this would allow you to draw cards indefinitely.

It's important to understand that these cards on their own aren't necessarily problematic or too powerful. The problem arises from the synergy of having many such cards in the same deck.

Obviously it is impossible to have a deck with nothing but Inspiring Presence, because there is no set of items with only those cards. But there are sets of real items currently in the game which do allow other infinite-draw builds. Here is one example, created by turinturamba. (I'll quote the cards from this example shortly.)

The key feature of an infinite-draw deck is that playing each of the cards in the deck must allow the player to draw at least as many cards as are in the deck. For example, Inspiring Presence allows the player to draw 3 cards; Demonic Feedback allows the player to draw 1 card; Spin Around allows the player to draw 1 card; Hot Spot doesn't allow the player to draw any cards. If you add up the number of cards that can be drawn by playing every card in the entire deck, you can determine whether or not it is an infinite-draw deck. A deck of 36 cards which allows the player to draw 37 cards is an infinite draw deck. A deck which only allows the player to draw 25 cards is not*.

Note: effects which require some condition or delay for the player to draw a card typically cannot contribute to an infinite combo. For example Accelerated Thought and Consecrate Ground cannot contribute, because they both require the player to end their turn in order to draw a card. Similarly, Martyr Blessing and Parry cannot contribute, because they both require the enemy to attack in order to draw a card. Thus these four examples would count as 'draw zero' for this analysis. On the other hand, Cleansing Ray would count as draw 1, because the player may be able to supply themselves with terrain attachments to cleanse. Similarly, Demonic Feedback would count as draw 2 regardless of the damage it does. The damage isn't a problem because it can be absorbed / healed by other cards (eg. a single Impenetrable Nimbus is enough to negate all of the damage from unlimited uses of Demonic Feedback.)

So lets go through the cards from one of the characters in turinturamba's build to count how many cards they will allow us to draw:

4 x Devastating Blow​

1 x Charge​

3 x Demonic Feedback - draw 2​

1 x Flimsy Block​

2 x Spin Around - draw 1​

3 x Altruism - draw 1​

1 x Mail​

1 x Parry​

3 x Demonic Revenge - draw 1​

1 x Slowed​

3 x Unholy Power - draw 2​

1 x Simple Bash​

2 x Leadership - draw 4 (and discard 4 unhelpful cards)​

4 x Bash​

6 x Inspiration - draw 1 (+ 0.5 with Altruism)​

Adding these up, we get 3*2 + 2*1 + 3*1 + 3*1 + 3*2 + 2*4 + 6*1.5 = 37. So with this build we can draw 37 cards, and since that is more than the 36 cards in our deck it is an infinite-draw deck. Note that it is generally unimportant which of our character actually draws the cards, because we can assume that the other characters are using either the same deck or some other deck which can make equally good use of the card draws.

[... to be continued in the next post]

 

[continuing from the previous post...]

What can be done to prevent infinite-draw?
Clearly it would be possible to introduce new game mechanics which prevent infinite-draw from working. For example there could be a rule that simply prevents more than, say, 8 card from being drawn by any one character in any one round. But I think it's better if we can prevent infinite-draws without introducing any new arbitrary ad hoc rules.

I believe the best way to prevent infinite-draw decks is to simply make sure there is no possible set of items which have enough draw cards to create an infinite-draw deck. However, clearly it would be a chore and a burden on designers if they had to re-evaluate every possible item build to look for infinite-draw decks every time they add a new item or change an existing item. So I've come up with an easy-to-follow rule for item design which, if honoured, would ensure that no infinite-draw decks are possible. The rule is this:

No single item should allow more cards to be drawn than are provided by the item.

For example, a three card item should not allow any more than three cards to be drawn; and a six card item should not allow any more than six cards to be drawn. (Technically, to be completely immune from infinite-draw builds, the rule should be that items don't allow even allow an equal number of cards to be drawn. But I'm confident that the rule wouldn't need to be that strict to be effective; and I'd prefer to not be so restrictive about what items are possible.)

If there were no items in the game which allowed the player to draw more cards than are on the item, then clearly there would be no set of items which allowed the player to draw more than the 36 cards in their deck. So if this rule is followed when designing items, then infinite-draw will not be a possible.

Important note: when counting the number of possible cards that can be drawn, we should always consider the ideal usage of the cards. eg. assume that we can handle any self damage from Demonic Feedback; assume that we have a full team of dwarves if we're using Dwarven Battle Cry; assume that all our characters will be in range of Inspiring Presence; and take into account any traits which could result in additional draws. Cards such as Talented Healer and Altruism complicate the analysis somewhat because they add draw effects to cards which usually wouldn't have them. For the ideal case, we must assume that the character has access to both these traits unless we are certain that there is some other game rule or effect which prevents the character from having them. For probabilistic effects (such as from Altruism), we should use the average number of cards drawn.)

As a final example, lets consider the items used in turinturamba's build to see which of the items violates my rule:
Aureate Mace: 6 cards, 3 draws (from Inspiration with Altruism)
Inspirational Mail: 3 cards, 3 draws (from Inspiration with Altruism)
Heavy Wooden Shield: 3 cards, 0 draws
Spinning Top Boots: 3 cards, 2 draws (from Spin Around)
Demon Charm Of The 2nd Circle: 3 cards, 5 draws (2 from Unholy Power, 2 from Demonic Feedback and 1 from Demonic Revenge)
Advanced Flexibility: 3 cards, 8 draws (8 from Leadership)
Focused Piety: 3 cards, 3 draws (from Altruism)

So there are just two items used in this build which violate my rule, and thus make this particular infinite-draw deck possible: Demon Charm Of The 2nd Circle and Advanced Flexibility. (Note that turinturamba use Demon Charm Of The 2nd Circle in every divine item slot.)

This doesn't necessarily mean that Demon Charm Of The 2nd Circle and Advanced Flexibility need to be changed. It's not necessarily a catastrophe if an item violates the rule. But it is important to understand that any item which violates the rule creates the risk of an infinite-draw deck. And in this case, it is these two items that make turinturamba's infinite-draw deck possible.

Regarding Leadership; although this card requires the player to discard 4 cards in order to draw 4 cards, that doesn't negate the problem. Remember that we need to consider the ideal usage of each card for the rule to be reliable. In the case of Leadership the ideal usage is that we discard 4 draw zero cards from our hand — cards that we no use to us anyway — and thus the discards don't negate the fact that we can draw 4 new cards. This makes Leadership particularly problematic because even if there was only 1 leadership card on any human skill item, it would still be a draw 4 card on a 3 card item and thus violate the rule.

A variation on the golden rule.
The rule I proposed is that every individual item should not allow more draws than it has cards. This rule is sufficient to guarantee that no infinite-draw builds are possible, but it isn't the only way. And as I pointed out, with that simple version of the rule it is not possible to have Leadership on any human skill item without violating the rule. So it may be worth considering adjusting the rule so that it can guard against infinte-draw without completely prohibiting Leadership.

One possible variation on the rule is to assign each item slot with a particular draw quota, and just make sure that the sum of those quotas is less than the total number of cards. For example, the total draw quota for priests could be assigned as follows:

2x divine weapon - 4 draws each
3x divine item - 3 draws each
1x divine armor - 4 draws
1x boots - 2 draws
1x shield - 2 draw
1x divine skill - 3 draws
1x race skill - 8 draws

In this case, I've reduced the allowable number of draws for divine weapons, boots, and shields; and given those additional draws to the racial skill and to divine armour. Any kind of distribution like this is just as effective as the original rule so long as it is applied consistently to all items. (eg. in this case the rule would disallow any kind of shield which allows the player to draw 3 or more cards.)

With the distribution I've chosen here, I think you'll find that almost every item in the game is already allowable, including Advanced Flexibility. But Demon Charm Of The 2nd Circle would still violate the rule, so I suggest that item be changed.

Finally, let me just reiterate that the kind of rules I'm proposing for item design are not the only way to ensure against infinite-draw decks; but it is a relatively simple approach which doesn't require any changes to the game mechanics and which doesn't require item anyone to study every possible item combination to see if there are any problematic cases. I strongly suggest that a rule like this be adopted and enforced - and that any items violating the rule be modified so that they are compliant.

That's all.

--

(* Note: it is actually possible to create an infinite combo even if the total number of draws for the deck is slightly less than 36, because cards that are in the player's hand already don't need to be redrawn and thus don't need to be part of the infinite-draw combo. Because of this, it may be wise to keep the total draw quota below 32 rather than 36 - to account for the 4 cards that a player can have from their deck at the start of any one round without any bonuses. This is not something I've considered in detail for this analysis.)

 

Bravo. +1.

 

While there is obvious work put into this (and I commend you on that!) I can't say I agree with you on a lot of the points/math.

For instance, you say, "Cards such as Talented Healer and Altruism complicate the analysis somewhat because they add draw effects to cards which usually wouldn't have them. For the ideal case, we must assume that the character has access to both these traits unless we are certain that there is some other game rule or effect which prevents the character from having them" yet, the build you examine does not have access to talented healer.

As for your solution, if I have both Talented Healer and Altruism active and cast a healing spell on a wounded ally, that could be a 2 card draw, so by your rule you would not be able to have more than one heal on any given item unless it's a weapon, in addition they couldn't be combined with any other holy or card drawing spells. This creates a very limited pool of options and drastically changes the way healing impacts the game. ie. it would have to be much larger heals to offset the number of heals available to a character while keeping the same general level of healing available.

Not saying it's bad by any means, but seems like it still needs some work.

 

@Blindsight, if both Talented Healer and Altruism are allowed, divine items would only be allowed to have 2 heals. (Altruism only adds 0.5, and so each heal would be worth 1.5.) But I agree that that would still be overly restrictive; which is why I think it's important that the people designing the items make a deliberate and careful choice to never allow those two cards on different types of items, nor allow them to appear together on the same item. Those are the kinds of additional rules I was referring to.

 

Not to complicate things but Leadership, Demonic Feedback and Unholy Power don't self target. So in effect it doesn't matter how many of them you have in this character's deck since they can't draw him any more cards, his team's builds are what matters. That's why these tend to see multiple priests in these builds (often 3 for the most card drawing).

 

This is somewhat of another issue I had with the analysis. At times it appears that he considers only a single character deck for determining rations, yet the draw ratios are taken from all team draws. He said that his assumption was that the other decks make the same use of the cards as this one however, so it's in line with the analysis -- it's just not completely spelled out.

Assume that all three characters have the same builds and the card drawing rations theory works.

 

First off, kudos to the OP...well thought out. Spotted a few inconsistencies:

Seems like there's some mix-up with Demonic Revenge and Demonic Feedback.

Agree with the infinite draw problem, but I disagree on the approaches towards solving the issue via draw quota design. My argument:

a) Players interested in maxxing their draw quota will still do so AND a large part of the deck still gets drawn even if its not infinite draw. It doesn't solve the annoying MP issue, ie, draw quota is not a solution to infinite draw. It is simply a throttle.
b) There have been many card redesigns (talented healer, leadership, altruism etc) in beta. Every new card brought in is going to break the draw mechanic over and over. This just creates a cycle of 'introduce new card >> draw build breaks >> over-nerf >> shelved'. Eventually, the design space is going to run out...what then ?
c) Damage from drawing cards should not be avoidable. Demonic Feedback/Revenge/Pain need redesigns to bring them in line.
d) I maintain the view of introducing draw build counters instead of limiting the design space. Let there be a penalty or an entire subset of cards/deck that penalize the opponent's draw build. Make the opponent think twice before building 3 x mill priests.

 

Here's my impractical solutions because I dislike the entire idea of the Infinite Draw deck:

Card: Pale Horse
Type: Attack
Effect: 1 damage for each card in hand - this damage cannot be mitigated.
Range: All characters
Trigger: 3+ activates on opponent drawing a card.

Card: Ying / Yang
Type: Effect
Effect: You may take a turn.
Range: Global
Trigger: 3+ activates on opponent drawing a card.

Card: Hubris
Type: Block Any
Effect: Opponent discards hand and attachments
Range: Block
Trigger 4+

Card: Mutually Assured Destruction
Type: Effect
Effect: All players discard their hand and attachments
Range: All Characters
Trigger: 1+ activates on opponent drawing a card.

Consider my spleen vented...!

 

Impractical solutions you say? How about these?

Card: Race to Infinity
Type: Boost (Trait)
Duration: 3
Effect: Whenever an enemy character draws a card during the round, you and all allies draw a card.

Card: Stop That!
Type: Utility
Effect: You pass. Your opponent is forced to pass.

Card: It's Silly!
Type: Utility
Range: All Characters
Effect: If the number of cards in your hand exceeds 5, discard your hand.

Card: Something Completely Different
Type: Attack
Range: Global
Effect: Squares under enemy characters become Mud Terrain. All enemy characters discard their hand. For each card discarded put a copy of the card into your hand.

 

As any M:TG player will tell you, the strongest thing you can do that doesn't immediately win you the game is draw cards. More cards equals more options, more options equals better options, better options leads to better plays. There is a reason that M:TG tournament players rely heavily on card advantage when building their decks. Generally speaking there are 2 types of card advantage, the first being cards that draw more cards than they cost to use, Demonic Feedback, or a card that generates some usually minor beneficial effect while replacing itself Spin Around etc. The other type of card advantage are cards that cost your opponent more resources than it costs you to play them, target opponent discards 2 cards, for example.

As a general rule, cards that punish your opponents for drawing cards are an ineffectual counter strategy because A. you need to draw the card in order for it to do anything, B. unless all your opponent's deck does is draw cards it is fairly easy to play around, C. cards like this don't usually generate card advantage themselves and D. these types of cards generally don't impact the game state directly which can actually lead to card disadvantage.
Given a choice between drawing 2 cards or forcing your opponent to discard 2 cards it is always more beneficial to draw the cards yourself.

That being said there are really only a few options for dealing with this problem. The first is to give every race/class the ability to draw a number of cards limited by availability of those types of cards, i.e. only available on racial/class skill items. The next is to remove card draw as a mechanic from the game thereby once again putting everyone on equal footing and removing the potential for abuse. The last way is to tack on more rules, add cards that specifically combat card drawing (which run into the problems i mentioned earlier) and generally making the game more complicated, and not in a good way, i.e. hard cap per cards played per turn, unholy damage being penetrating and/or reducing max hp instead of dealing damage, or cards like Mind Blast - arcane 3 damage, range 6, penetrating, opponent discards 1 card per each damage dealt to them, attach this card to the opponent duration 2.

The fact that "bury your opponent in an avalanche of card advantage and make the game completely one sided" is a "viable" option in either single or multiplayer reflects poorly on the health of the game. Usually card games don't run into this sort of problem until after they are well established and are intentionally trying to design OP cards in an effort to move product.

 

The counter to infinite draws cannot itself be a card because infinite draw decks will still dominate unless you devote as much of your deck to stopping them as they do to drawing or unless the counters are so common that they are part of every deck without specifically building for them. That involves adding text like, "...and all characters must discard down to 4 cards." to a lot of unrelated cards and it really muddies the design of the game.

Unless they want to do a massive card rebalancing focused around this and be forced to take it into account every time they introduce a new card-drawing card, the solution has to be in the base mechanics of the game. A hard per-round limit on draws and/or a max hand size is the easiest way to fix it but it's hard to explain to a new player how it works and why. Yes, people will still go for card advantage, but that's just part of card games.

Spitballing, my first attempt at a fix would be a hard limit of 7 draws per round and a max hand size of 7. Along with this, i'd probably give certain weak card cyclers a better secondary effect. For instance, make Spin Around a keep card that allows you to change facing (maybe on a 2+) at the end of each of your turns, but discard to draw a card. I'd make Lateral Thinking a 1-card version (self-included) of Leadership.

 

You've done a great job explaining the problem here, and I think your suggestion of adopting a "draw quota" for items based on item slot is the most elegant solution (As well as being the quickest solution to implement - all they'd have to actually do for now is nerf Demon Charm Of The 2nd Circle).

Having the counter be specific cards would mean that everyone would have to build their deck to counter infinite-draw decks, and hope they get the cards they need before their opponent's hand size explodes and you stop getting turns.

I also think it's probably a good idea to make the damage from all these traits unpreventable. Make all of it psychic damage, and make it so psychic damage ignores impenetrable nimbus if it doesn't already.

 

I'm pretty new here, but as a long-time MtG and Dominion player I'll say this: A 36-card deck is tiny. By definition, it makes any card draw more powerful than it would be in a 60-card MtG deck. There's less chaff to get in the way of the good stuff, especially if I mostly rely on the racial move card for mobility and intentionally run light on movement.

As to how that relates to Card Hunter: I *really* don't know what I'm doing yet, and I'm only really playing the campaign -- I'm jumping all over cycling cards generally, even if the secondary effect is fringy (such as Spin Around), or if it's a drawback card (Demonic Pain) -- I don't really mind the Demonic Pain drawback too much unless the priest is super low on hp.

Again, I don't know anything, but I'd assume once you get decent gear that card cycling is king.

 

a) I think there's a profound difference between a deck that can cycle a lot, and a deck that can cycle indefinitely. The way I see it, the advantage gained by cycling / drawing cards is asymptotic. ie. draw-card effects synergize in such a way that they become more and more powerful as you get more of them, and if you can reach the point of an infinite-draw deck then you become undefeatable - because the other player simply won't get to play another card for the rest of the game. With the kind of quota system I'm describing may not stop people from loading up one card-cycling abilities, but it will at least stop them from reaching that undefeatable point. And if the deck can't quite reach that infinite-combo, then at least the other team will get a chance to try to counter them; and the owner of the draw-deck will have to make a real effort to deal with all of the negative effects and traits on the cards they've loaded up on - and they'll have to bring proper offensive cards, because they won't have the option of winning in a single round just by playing a single crumby attack over and over again.

b) The key idea that I've tried to describe in this thread is that we should have a set of guidelines for the game developers to use when designing or changing items. If anything, I think these guidelines would make it easier to change existing cards and items, because there would be a systematic way to evaluate the changes to see if they are likely to enable infinite-draw decks. eg. Supposing we want to change the effect of an existing card; If the new version has equal or lower card-drawing potential to the previous version, then we can be confident that it won't cause infinite-draw problems. If it has more drawing potential, then we should re-check every item that the card appears on to make sure that they aren't going over their draw quota. If the new card adds a draw effect to existing cards (similar to Altruism or Talented Healer), then we must reconsider every possible card that is affected. (This may be a massive chore, but that's because cards like this can potentially have a massive impact on the balance of other cards.) So I think a system like I'm suggesting would help designers of cards and items to feel a bit more confident at least about this one aspect of game balance.

c) If you want to nerf the cards because they are too powerful, than changing the damage to 'psychic' type would probably be helpful – and maybe the cards do deserve to be nerfed. (I certainly think that Demonic Feedback is more powerful than its 'paper' rating would suggest.) But generally speaking, the problem of infinite-draw decks isn't able the balance of individual cards - it's about the entire deck. Cards like Demonic Pain are not too powerful. In fact Demonic Pain is a disadvantage in most decks — but when combined with 30 other draw-card effects, it somehow becomes extremely powerful. Also, I think it generally adds depth to the game when the disadvantages of cards can by negated by other cards - so to me that one reason why it might actually be good that the damage from these cards is avoidable.

d) I don't think counters can ever work effectively against infinite-draw decks; because the player trying to counter the infinite-draw might simply not draw their counter cards in time before its too late. (Or they might draw it, and discard it before they realise it is needed; or the counter might be removed or prevented by positioning or something like that.) Perhaps it would be good if there were cards that punished the other team for drawing cards; but I don't think it's the solution to the infinite-draw problem.

As a side point, I'm starting to think that cards such as Talented Healer and Altruism should be kept out of the game, because their impact can be so far-reaching and difficult to measure in terms of balance. For example, in most builds Altruism isn't a very powerful effect - but as we've seen, in one designs their deck to exploit it then it can create an infinite-draw deck. Meanwhile, although Talented Healer may not be a key culprit in this particular infinite-draw deck, it does have the potential to turn very weak cards such as Minor Heal into very powerful cards. Talented Healer it is widely recognised as being too powerful; and the majority of its power is unlocked when combined with otherwise inconsequential healing cards and items. As I pointed out in the original post, Talented Healer and Altruism complicate the analysis and balancing of other cards. So rather than constantly wresting with the balance effect of these two cards, I'm thinking that perhaps it would be best to change both Altruism and Talented Healer such that their effect isn't to draw another card.

Thanks, I'll fix that now. There were a bunch of other mistakes when I first posted it too, and there may still be more. Actually I'm starting to suspect that the footnote at the end of the post might be a mistake, in the sense that I suspect the effect of simply starting with cards at the beginning of each round might be more important that I first released. It may be wise to limit the total quota to 32 draws rather than a full 36, or else risk a luck deck order being enough to set off an infinite combo even with the rules in place.
[edit] Ok. I've changed the revenge/feedback thing, and I've edited the final comment at the end. I generally don't want to make too many changes to the OP though, because I changing it after people are already discussing it can mess up the flow of the discussion.

 

The devs want a game that plays briskly, right? My suspicion is that removing something like 60-80% of the cards that have a draw effect would alleviate the infinite loop problem and make the game faster overall. Would that negatively impact the strategy element of the game in a way that I haven't figured out yet?

Does anyone have a link to a discussion as to why the devs decided to include as much card draw as they have to this point? Or why it is that priests got the best card draw? Was it intended to help cycle for healing cards? Or a utility function to bump up the class power?

Late edit thought: Maybe the right answer is to remove the traits that draw cards based on heals and to give priests a card(s) like "Lay On Hands" - Range 1, Heal 5, Draw a card.

 

It is, as the main difference between Magic and Card Hunter is that you can't lose by decking out, i.e. running out of cards in your draw deck. "Infinite Draw" in CH is really an infinite draw, it's not ended at drawing card 36, you could and in theory could draw through your deck several times.

 

Not going to address the bulk of arguments, nothing new there. More than aware of the difference between infinite draw and high cyclers. Just wanna address some key points.

In the first place, there is no need for another set of design rules. Nothing fundamentally wrong with the items, cards need some rework to make them less abusable. Dominant builds with no in-game counter is the problem. Make those counters available and the dominant build gets challenged. This maintains the diversity and keeps the game interesting.

Completely do not agree. I have played counter-mill vs classic mill. Just as you can draw to draw more draw-cards, I can draw to draw more counter-draw cards. There are several other gameplay strategies to counter mill decks, its just that atm...these options don't exist in Card Hunter. The recent War Cry change might help to one-shot priests but that's only 1 option.

Again do not agree. A player made a dominant build, give players options to take that build down. Don't blame the cards or their synergy for being strong. I really don't want to see this game devolve into some stone age ccg.

 

This isn't about one player and one build, and I really don't think Altruism and Talented Healer are what separates this game from a 'stone age ccg'...

Regarding synergy, I think it's important that we all understand that cards that allow the player to draw more cards creates a special kind of synergy which is fundamentally different from other kinds because it can synergize with itself. This creates a kind of feedback that can easily scale out of control. The distinction might not be obvious to everyone, so I'm going to take some time to try to explain it with maths and graphs.

I'm going to make some simple graphs to illustrate how synergy affects the value of two very simple hypothetical decks. I'll be using very rough approximations in these examples to keep all the maths simple. The key point I'm trying to make has nothing to do with size of the numbers or the accuracy of the approximations, so try to focus on that. The key point is in the shape of the graphs. In particular, the point is that most synergy between cards has limits whereas the self-synergy from drawing cards does not.

To start, with lets consider the basic synergy between Unholy Frenzy and Weak Strike. If you have a bunch of Weak Strike cards in your deck (for whatever reason), then a gaining access to Unholy Frenzy is a massive boost. The damage boost can double the effectiveness of the attack (or even more than double if the enemies have armour). So that's a kind of synergy where one card can boost the effect of another.

Suppose you want to rate the usefulness of each card in your deck by using some kind of rough scoring system. Perhaps you'd do this by saying each point of damage you can deal to the enemy is worth one point. In that case, each Weak Strike would be worth 2 points, and each Unholy Frenzy card would be worth 2 points for each Weak Strike it can be applied to.

To give us a rough sense of how this kind of synergy affects the deck as a whole, lets imagine we have a 36 card deck consisting of some number, say x, Unholy Frenzy cards, and 36-x Weak Strike cards. (eg. if x = 6 then we'd have 30xWeak Strike and 6xUnholy Frenzy). The total score for this deck would be

x * (value of unholy frenzy) + (36-x) * (value of weak strike).​

To keep the calculation simple, I'll estimate that each Unholy Frenzy has the opportunity to boost 4 random cards from the deck. The boost is 2 damage for Weak Strike, but no boost for other Unholy Frenzy cards. So then the value of Unholy Frenzy in this deck is

4 * 2 * (36-x)/36.​

The '4' refers to the 4 cards that can receive the boost. The '2' is the 2 damage bonus. And (36-x)/36 is the probability that a random card from the deck will be Weak Strike (and thus receive the boost). With this, the total value of the deck is

x * 4 * 2 * (36-x)/36 + (36-x)*2.​

Here's a graph of the total value with respect to the number of Unholy Frenzy cards in the deck:



As you can see, the total value goes up; reaches some optimum value; and then drops down to zero as the deck runs out of attack cards.

Most synergy in the game works in a similar way in that some cards become more useful in the presence of particular other cards. For example Firewall on its own would have some expected damage output based on how likely it is that you can get the enemy to stand on the lava at the end of the turn. And you can boost that expected damage with Entangling Roots by preventing the enemy from escaping. The numbers and calculations would be different, but the general shape of the graph would be the same.

Now lets consider the synergy from having cards which draw other cards. For simplicity, imagine there is a card called 'draw-2' which when played simply lets us draw two cards from our deck. And lets suppose we have a deck of 36 cards consisting x 'draw-2' cards and 36-x Weak Strike cards. Again, lets calculate the total value of this deck, assuming that each 2 damage attack is worth 2 points.

The value of the 36-x Weak Strike cards is (36-x) * 2 - because each card is a 2 damage attack; nothing special there. But here comes the important part: the value of each draw-2 card is the average value of the next two cards that are drawn. So the value of a draw-2 card is
v = 2 * (2*(36-x)/36 + v*(x/36) ).
In this equation, v is the value of a draw-2 card in our deck. The first '2' refers to the fact that we're drawing 2 cards. '2*(36-x)/36' is the value of a Weak Strike (ie. 2 points) times the probability of drawing a Weak Strike ((36-x)/36). The next part is the the value of a draw-2 times the probability of drawing a draw-2.

As you can see, we've got v on both sides of the equation, and so to work out the value we need to rearrange it like so:

v - v*2*x/36 = 4*(36-x)/36​

v*(1 - x/18) = (36-x)/9​

v = (36-x)/(9*(1-x/18))​

v = (36-x)/(9 - x/2)​

That's enough rearranging. We can see what's going to happen now. As you can see, if there are 18 or more of these draw-2 cards in the deck then the value is unbounded. Using this result, here's a graph of the value of the whole deck with respect to the number of draw-2 cards:


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So hopefully now you can see why I think this kind of synergy needs special consideration and special precautions in terms of game design. The power of drawing extra cards is recursive, ie. it is self-referential. Its power goes up and up the more you can do it. No other synergy in the game is like that. This isn't about one item being too powerful, or about one card being too powerful; and it certainly isn't about one player making a powerful build. This is about a balance problem that arises from having cards that allow the player to get more cards. It creates a feedback loop which can scale out of control if there are enough of these cards.

What I'm suggesting is that there should be some design guidelines in place to prevent this from happening. Without a systematic approach, balance problems arising from this are just going to keep coming up again and again.

 

I find it improper to compare to some other CCG, and not even say which other CCG, as a defense for a particular strategy being acceptable. Especially when you go on to say that the counter doesn't exist at all.

First off, that means you ALSO think a change needs to be made, you just advocate adding something new instead of changing something existing.

But more importantly, without saying where you played this anti-mill deck with another mill deck (which is what you describe, being able to infinite draw against their infinite draw) we cannot evaluate your stance as valid. We have no concept of how similar your other game is in mechanics to this one.

I cannot think of any card you can create in this game which will shut down an infinite draw deck reliably. Because it would have to include a card which does this thing. If you only have one, then you have to get lucky and pull that card in time, let alone choose to include it in your build at all. And either that card is in your hand (which priests can force you to discard) or it is attached to you (which priests can remove).

Now, if Talented Healer made the priest draw a card AND the nearest enemy... that would counter the infinite draw quickly.