Oh. Yeah I just can't help but get shitty roommates. ;)

In all seriousness though, I was completely intending on sticking with my original U/R build, but then I remembered Praetor's Grasp was a thing that I loved, and I was kind of hellbent on putting it into the deck, even if it meant I had to go away from Izzet. And then there's Ashiok, Nightmare Weaver, which is a revolving door in this deck. :P

I've decided that Brain in a Jar from the recently spoiled Shadows over Innistrad stuff will most definitely be finding a place in the deck.

On the chopping block: Diluvian Primordial.

Monsmtg it's back, baby! :D

Yay! No ones ramen is safe!

For anyone coming here via my posts, here is a list of the cards (minus the mana base) that I'd be adding if I switched from Izzet to Grixis:

Ashiok, Nightmare Weaver
Mindleech Mass
Fiend of the Shadows
Praetor's Grasp
Memory Plunder
Wrexial, the Risen Deep
Silent-Blade Oni

If I figure out more, I'll add them in a later comment.

Nothing to comment on the Grixis switch, but I've seen Sphinx-Bone Wand work wonders in a deck like this with Melek, Izzet Paragon at the helm, and it's budget.

Personally I'd keep it UR, the cost of adding the third color unless you already have the duals will be hefty. Just make an alternate deck with those cards/theme and Lazav, Dimir Mastermind at the helm. It'll be cheaper and both decks will probably play smoother.

One card I suggest either way is Aqueous Form, both the scry and unblockable are amazing for this kind of deck.

chapman.luke27 that's a possibility. I'll test it out and see where it goes.

dlamars that might be what I end up doing. I know I already have a Lazav, Dimir Mastermind lying around somewhere.

Nice! +1 from me! I have a similar deck called "Would You Kindly".