Fantastic game, so much fun! Are you going to add cards from the other acts, or make custom cards? If you want I can help with card balancing, I make my own card games and have played a lot of the original.
Now that I've gotten the fanservice out of the way, I noticed some things:
-Stim Mage and Bone Heap don't attack when their stats are buffed. And their attack stats reset every turn, though if this is intentional (which I think is a great idea) it should be explained in the abilities.
-Force Mage is way too strong in a multiplayer setting, I think it should have Gem Dependant to give your opponent a way to counter it.
-Some cards don't show up when sorting through the deck editor. I'm not sure if this is a glitch or designed not to show broken cards.
-You should be able to hover over and read card abilities while in a battle. This is mostly for new players, which would make it easier for them to get in, and not require the experienced player to explain every card three hundred times.
-Any and all abilities should be written and explained on the card. This isn't base game Inscryption, secret/hidden mechanics only hinder a multiplayer setting.
-Another glitch is that spawned/Summoned cards, created by other cards, are extremely big.
-Finally, some cards like the Opossum and Zombie are the exact same, there should never be a case like this. Other than flavor or swarm, why use one or the other. Maybe make Opossum a 2 Bone cost, 1/2, with Bone Digger?
These are just some thoughts and bugs I noticed while playing with a friend. You are doing great work, and don't take this the wrong way. These are merely suggestions from an overly excited fan! I hope you continue to update this and make it great! THANK YOU!!!