I suppose this is a "prompt bug." When The Pools of Slime appears, Gary says "Those pesky jellies and slimes are up to more skulduggery!" but I THINK the sound file is Karen's. It went by a bit quickly for me to be sure.
You were right on both counts, this is a prompt bug and it was playing Karen's voice... She used to have that line. Fixed for upcoming release, thanks!
In regard to GM prompts while looking at a battle description: how does the game keep track of which prompts you've heard? Up until now, I'd noticed that I can click through those prompts, then quit without entering the battle, then reload and read the prompts a second time. Handy if I wanted to re-read some turn of phrase. However, today in Shrine of the Astral Guardians, I found an issue at the second battle. I clicked through Karen's text, then quit without entering the battle, then reloaded . . . to read some DIFFERENT text where Karen suggested a cosplay outfit for Gary. Where was that text supposed to play? The third battle? Because I subsequently received no prompt before the third battle.
Some of it is tracked by beating adventures, and some of it is tracked by unlocking adventures. Once you've beaten or unlocked the adventure it is connected to, you should no longer see it.
Okay, but was what I saw a bug? It looked like I read the next section's text early due to exiting and re-entering. Also, something else: when unlocking CardStock II Secret Preview on the map, Melvin's prompt keeps you from scrolling the map. You can sit there looking at his "Do you dare" speech with no "continue" button, and you CAN click on adventures, but can't scroll by dragging. If it matters, I got to this point without my party token on the world map. I'd exited and re-entered Card Hunter while fighting the dragon. Clicking on the adventure dropped my party in as normal.
I just went into the Chest Shop from the multiplayer menu and got this dialogue: You said it Gary; weird... Edit - additional information (seems I've gotten sloppy in my bug reporting since the game released): I had been to the first campaign chest shop and bought a chest as per Gary's instructions in the tutorial. However, I never actually clicked the "Take All and Continue" button to reset the shop and hence missed his "You can buy more pizza..." dialogue. The above was the first time I had set foot in the Chest Shop from the multiplayer menu and I don't think I've ever set foot in the second campaign chest shop.
I don't know without more information. Some prompts are also triggered on the world map, so maybe this is what you saw.
Sorry, I posted all that I know. I didn't come from the world map: I closed the browser while the last of the pre-battle text was up, then opened the browser and returned to Card Hunter, whereupon I saw the pre-battle screen as normal but this unexpected "cosplay" text. Also, did you recently add an explanation from Gary about a minor power token changing to your first major power token? Because I just saw that text when I received my third major power token (and I saw nothing back when I received my first).
Same thing happened when I beat Garnet Portal and Cockroaches unlocked. I don't think I quit the game in the middle of that battle, but I'm not sure. In Goblins in the Woods, Karen's prompt after the second battle appears in the middle of the screen instead of at the top.
In the Jewel of Alet Zhav, there's no prompt when you first visit, then before the first battle Melvin asks why we're still awake and there's no "Continue" button. When you start the battle, Gary says something which quickly disappears when the board appears. EDIT: I managed to capture the illusive prompt before the battle loaded, note the black background:
I don't know if its belongs here but I keep on getting a prompt that says "Gary" when I click near my first character during battle. numbers won't show up http://imgur.com/tz0i4qX Dang it Gary... http://imgur.com/fyvcbVG I'm using chrome....maybe its an issue with flash or something.
If you try to enter a league but do not get into a pod before the entry closes Gary will pop-up and tell you that you couldn't be entered into a pod and refunds the pizza. Later if you log in after the league has finished the league pop-up appears stating that the league is over and you won 0 games.
It also says you tied for first place but still didn't qualify for any prizes. Which is somewhat amusing, but not helpful.