I really like Ashiok, Nightmare Weaver and it fits this deck style. It's not super expensive, but it is more than $5.

Underworld Connections could help you draw into more ways to steal their stuff.

Baleful Strix is one of the best UB cards for commander.

Otherwise I love the deck! Keep it up!

Oh yeah, and Mulldrifter is pretty awesome too. Try it out!

How do you end up commenting right after me whenever I post in that thread? Are you like a psychic or something? Lol

Actually, Ashiok, Nightmare Weaver would go great in this deck. Sadly she can only hit creatures that she exiles, but that's still pretty damn beneficial especially in an explosive format like EDH. I'll take those others into consideration too. I really like the idea of Underworld Connections, especially when you take into consideration the fact that for a U/B deck, I have remarkably little card draw- just Dictate of Kruphix. I may add Howling Mine and Font of Mythos as well.

Considering the theme I'm surprised you don't already run Beguiler of Wills. Another great card that kind of fits the theme of the deck is Havengul Lich

Two cards that I actually don't own... Lol I wasn't playing much during Innistrad block so a lot of the clone/steal cards from that block, I just don't have. If I get ahold of them, they'll definitely go in. Thanks for the comment!

Your welcome, and its a good thing those cards are pretty cheap. I really love the deck because I also have a deck that likes to borrow my opponents stuff, except my general is Sygg, River Cutthroat.

My suggestion to steal your opponents creatures is the amazing blue card Willbreaker Target your opponents creatures with any spell or ability and then they are yours!

Willbreaker is amazo in decks where I actually have a lot of ways to target my creatures. Sadly, this deck really doesn't fall into that category. If I do end up including more target effects, the Breaker will definitely go in.