I figured it was most dmg in one turn, not in one action. Here’s a version for this challenge :
Strength / Blood / Future vs. Blood / Growth / X
Assume all units in play (51), Tech II & Lab = Blood & Future, assimilated opponents war drums & MoLaCs
Cast 2x Bloodlust, 1x Sensei’s Advice & use Sensei buff on a doubling barbarian for +8
Molac (20) + Casted buffs (8) + Drakk frenzy (2) + Drumz (50 x 8) + Base atk (3) = 433
Enemy base to -422