Nice idea, the wording of the 2nd ability needs to read

"Exile target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step." to clarify what happens to it. As written, you exile UEoT but then it sits in limbo wondering what to do next.

Just noticed that the 2 abilities are repeatable if you have enough mana open. That would make this a rare card. To be uncommon both abilities would need to include in their costs. You may be able to get away with just thye red ability including as the white one isn't destruction.

I really like the idea behind this