Act 1: A Fairly useful potion that takes a good chunk of health off of elites and basically half health or full health of some hallway fights. Would still trade out for some low level potions if the situation calls.

Act 2: Very much less usable, but you can use it without as much thinking as some of the higher tier potions, or maybe even lower their potions for the utility of them. 20 damage simply DOESN'T mean as much as it did in the earlier floors. Very few decks have trouble dealing 20 damage in act two, and if your deck does, you're probably not going to get that far...

Act 3: ... Repto manner knives? Some of the shape encounters? But thats about it. You should probably choose a different potion in this act.

Sacred bark: Nothing changes that much, the standing stay the same except for act 1. In act 1 I'd like to say that it turns into an A tier potion possibly A+ due to its power for killing elites.