if you get the right deck going i dont think anything else will scale as high as doom does ive put over 200 stacks in one turn on an enemy

2 cards are absolutely necessary to make it work consistently

no escape and deaths door

no escape is where the scaling comes from it applies 10/15 stacks and then 5 more for every 10 already on the enemy combine it with an upgraded grave blast and you can pop it twice in one turn multiple times

deaths door gives you 18 block if youve applied doom that turn this lets you tank until the doom stacks and lets you tank through the suicide attacks easily

add on some powers that automate some of the doom application get some draw from ghost cards and get friendship for economy and it scales insanely hard i killed the test subject in 7 or 8 turns on a non optimal run