First: I rate this game 10/10 for PERFECT game balance. I think wizard, poisonmage, dryad, and necromancer are slightly undervalued/OP, but only by a half-point (and they all have obvious weaknesses anyways).
Game tip summary for starters:
Easy pieces to use against AI are: bomber,snake, spearman,axeman,pawn,sylph,militia,princess, poisonmage,rook,dryad,paladin,necromancer, airElemental,queen,bishop. AI is especially bad against poison,bombers, sylph/airElemental,princess. Unlock Daily Challenges ASAP because it's main way to get coins/gems. As a general rule, higher tier pieces are better for their value by half-point. Poisonmage4 is especially good, and a month of arcane chests easily unlocks it. AI is REALLY bad against bombers as of 2020nov11 so use it as anti-AI insurance policy in your deck if you hate the AI.Play at around 2am EST to avoid other players and fight botAI more. I farm bot AI for pts. at that time.