Some of you may remember me raising quite a stink a while back about the Oblivion Ring + Vedalken Mastermind. I persist in my feelings that this combo should not work, but I've finally come up with something more constructive to do than complain. I humbly suggest the following template to the rules gurus; please let me know if it does what I want it to do (ie have Oblivion Ring work the same way it does normally, but not be abusable with the Mastermind and similar effects).
When Oblivion Ring comes into play, remove target nonland permanent from the game. If you do, return that permanent to play under its owner's control the next time Oblivion Ring is not in play.