Created while brainstorming sensible library enchantments. In what color does this belong? And, for that matter, at what CMC?

Also, I realize this isn't entirely sensible. It's cool, though, in that it basically gives you another hand, potentially of someone else's cards, in your exile zone. I considered adding a "discard" clause to make it even more like a hand, but that's too many words.

I decided that I actually like this in its current colors, though I'm not sure it actually needs the white. It's vaguely reminiscent of Sen Triplets, after all, if only at a great distance. Also, I'm making it cost 5cmc. EDIT: No, I'm making it 4cmc with double blue.

Hmm, it's a wonky cross of Moonring Mirror with Shared Fate. I like it.

I'm glad you're such a font of knowledge. I didn't even consider the similarity to Moonring Mirror, and I didn't realize Shared Fate existed. Now I know this effect is acceptable.

To me it seems more like Phyrexian Arena on layaway.

With the added benefit that it's a hand that you never have to discard from or reveal to your opponent, and also that you can steal your opponent's cards.