Absorbent is the worst champion modifier ever and Man in the moon is just tedium incarnate making it even worse, my strategy for the boss in general is always have a tanky cat that regenerates at minimun 10 mana pet turn so i cast "stop hitting yourself" and dont have to deal with lining up the hands and the other cats just focus on raping him, best if you can stack a lot of thorns on the cat thats gonna be vored. The other is bring some form of bruise and just completely cuck him out of his gimmick or bring a lot of DoT and wait until he dies of 500 poison.