I attempted to utilize multi-turn heal skill to somehow offset Cass death roulette even for just a bit, but to my frustration, after the next turn, the heal will activate first then death roulette with proc after. Thus rendering any healing useless. You will still end up with 1 hp when death roulette will proc for that turn. It seems devs really did want Cass sin skill to have no counter at all.
I will surrender to the fact that no nerfing is going to happen to Cass sin already. Since that is the case, the least you could do is to somehow adjust the settings of other classes or general arena mechanics to allow them have a bit some counterplay when fighting cass sin. For the multi-turn heal, configure death roulette to proc first then heal will come after.
If anyone has other suggestions to adjust arena mechanics of other classes in arena, you can share your thoughts also. Please consider my suggestion.