I imagine this to be part of a cycle of cards, one for each element.
Chaos Breach
5
Type - Shield (special)
Chaos Breach comes into play as if your opponent cast it.
Creatures that attack you are affected by Improved Mutation.
Chaos Rift
4
Type - Shield (special)
Chaos Rift comes into play as of your opponent cast it.
Creatures that attack you are affected by Improved Mutation.
So, this does a few things. Obviously it's a way to get massive Improved Mutations on your side. Kinda fun. But, it also will remove any shield your opponent has, including immortal ones. On the downside, your opponent doesn't need any PC to remove this, just casting another shield makes it go away.
