Rattlesnakes dont prohibit actions, but rather punish the player for doing it by either dealing direct damage, removing creatures, countering spells, etc
We have two examples of Cases to show you: Collect Evidence (New Mechanic From Karlov Manor ) Collect evidence is the next new mechanic from this set
Where it really shines is its ability to create a token copy of another attacking creature that you control when it attacks
There are a lot of cases in which you will need to individually search how a card plays to better understand the minutiae of their mechanics
FromTheShire: At least on paper this is a decent little way to snipe utility creatures using all of the artifacts this deck creates, the problem is that it's likely only a 3/3 so this can easily just be a one off removal spell
Cards in a powered Cube tend to fall into three buckets: the "fair" bucket, the "unfair" bucket, and the "broken" bucket