I can not get past this third fight of the new level 18 adventure. Obviously I could use crowd control or mass damage cards but what are the specific cards I should be looking for? Any strategies for the level itself?
Chops and good armor are a must. And if possible try to get everyone lined up with their backs against a wall. If the enemies can't attack from behind Sneaky Bloodsuck only does 5 damage. Add Reliable Mail to that and it's only 3. Then you'll have plenty of time to cut the annoying critters down.
There is a twist in the corridor right near where you start that gives you two corners to nestle yourself in - have your third character stand next to the one in the bottommost the the two corners. All your characters have LoS to each other, cannot be attack from behind, and only have 3-4 squares that can access them. This is a huge help in defeating the module. Aside from that, yeah, O.Chops, Frenzy and Reliable Mail are great. You can also get a fair bit of mileage out of Barbed Mail/Enchanted Harness, but that's much less easy to draw (or build for)