This may sound cliche or be a response that most would roll their eyes at, but my favorite card is Jace, the Mind Sculptor. Playing Mythic Conscription during its heyday and then switching over to U/W CawBlade before and after Jace and Stoneforge Mystic was banned, I have fond memories of the card and still can't help but smile every time I cast it. Even though it's only legal in Commander and Legacy as widely supported formats, I'm looking forward to the day when I acquire enough revised dual lands to be able to bust out my playset of Jaces once again and give Legacy a legitimate shot.
So yeah, my favorite card is Jace, the Mind Sculptor.
EDIT: Woohoo, 1500th post in this contest, which means that my chances of winning will eventually be less than 1:100. Oh well, here's to sick rips off of Jace's Brainstorm!
There's an Omnispell Adept in the Izzet one. Nothing of note in the Golgari deck. Wouldn't that have been nice for them to include an Assassin's Trophy? Haha
This was all contingent on this guy coming into play this turn and wanting to attack with it immediately. Yes, the blink protection and having shroud with Greaves is a little redundant, it was mainly to give it haste. Not being touched by targeted removal is just icing at that point.
I see that now. For some reason, I had only permanent cards on the brain that you could cast off this.