The poison surface is not the status effect on the person. It will be both poisoned and burning. So he'll take a lot of damage overtime.
Yeah you can stack up tons of AP enhancing spells but I usually find it breaking the RP I have for the character I have.
Because you can be elf Flesh Sacrifice + Adrenaline Surge + Haste then Use the source skill to play another turn and Skin Graft and do it again. And don't forget the trait to have + 2 ap when you kill someone.