Last deck I made was Memnarch.
Super dickish deck, but really fun. A buddy of mine runs a clone-heavy deck, with mirror gallery. He stole Memnarch, and then cloned him twice. Needless to say, because most of my deck is artifacts, I didn't last long.
Deck after that was Phage the Untouchable.
Super ridiculous deck. Lots of stuff to get around her ability. A lot of self-counters (and the graveyard recovery), Torpor Orb, Sundial of the Infinite, etc... Only been able to successfully cast her a few times, but it's a really fun deck to play.
After that was Sliver Overlord.
I don't play it that much though because fuck slivers. Note to everyone else though, going against a mill deck like Mirko Vosk fucking TRASHES this deck. I didn't stand a chance.
After that was Jenara, Asura of War.
I'm going to call it my Oprah deck. It's heavy on +1/+1 counters. "You get a +1/+1! YOU get a +1/+1! Everyone gets a +1/+1!"
And today I'll be testing my new one, Kaervek the Merciless.
Which will hopefully be extremely fast and high aggro, but we'll see.
I want to run a Rhys the Redeemed token deck someday too.
That was the first EDH I wanted to make, but none of the local shops have him, so I settled for Memnarch.