as you could probably guess from the name, sacrifice cards are cards which require you sacrifice or give up something for a benefit in another place. The example i used to illustrate the idea is a flat decrease in extraction speed for movement speed, but the idea is to have people consider what sorta end game are they going for, like would they rather have worse stats for the rest of the run but have an extra max heart, should they extract slower but give the distractors better movement, maybe you find blackouts to be really annoying so you wanna remove them all together but now ichor leaks are twice as common. The wrong choice can easily ruin a run but it has the potential to allow for certain toons to get massively buffed, like having distractor brighteny be more valid with “flight response”