First commentor missed the Cassandra side effect: you can do nothing to change it and no one believes you.

You can see a person's next move at the expense of generating negative causality, wherein large objects are attracted to you at high speed. See the man unwrapping a sandwich? Boom, hit by a bus/piano/anvil/whale.

Anytime you use this power, immediately afterwards you feel everyone in a half mile radius's feelings at 200% intensity at the same time.

But it hurts like hell and you are in pain the entire time you shapeshift

Every time your past self reads one of your messages they ~~loose~~ lose the ability to read one word forever.

But you stink like a skunk every time you turn invisible.

You never get to use the power for your own enjoyment because people will never leave you alone…you will constantly assaulted with questions because everyone knows you have the answers. You have no peace.

You become completely physically disabled, almost a complete vegetative state, and can't physically do any of it.

The summoning makes you feel nauseous