Hmmm........ the law is "anything that can go wrong will go wrong" so here are my ideas:
1) the next creature played will have an effect put onto it, I don't know which one: antimatter, gravity pull, poison, immaterial, basilisk blood, maybe a random effect?
2) the next permanent played will be put on the opponent's field
3) the next creature played will be put back in the deck
I will put more when I come up with something.
Note: all of these would work for the next card played by anyone, though maybe the upped version could only affect the opponent.