Final boss on my Heroic ‘all spells cost 2 less’ anomaly run was the paladin character. He used Sound the Bells! I thought it would continue on forever, but after a while the AI stopped and let me have a crack. Fortunately, I had Antonidas out and could close the game through face burn! XD
Not sure if this is something the dev team want, but could make heroic paladin hero runs, when it’s released, a bit too easy.
I think the AI is programmed to do a maximum number of actions during each turn, just to make sure that it will not get stuck in an endless loop if they ever get a 0-mana echo card.
I personally doubt that the dev team will want to prevent this for players, in the past they have allowed other weird infinite combos in solo mode (just as long as they require some RNG and can’t be pullled off consistently).
This is fixed, no more spells cost 2 less, so it’s much harder now.