I used to have a deck around Scuttling Doom Engine casting it, swinging, trowing it in the graveyard and then get it back with Trading Post. It was fun but didn't really work well.Then I played against a friend and his EDH deck with Feldon of the Third Path as his commander and got my ass handed to me.Basically trew both ideas together and came up with the following deck. So far I'm pretty happy with it. I useFeldon of the Third Path and Goblin Welder to bring big threaths back from my graveyard and try to have stuff in my graveyard that give me answers to most problems :
Utvara Hellkite : if I need an answer to flyers
Myr Battlesphere : if I need a lot of tokens/blockers
Dragon Mage : If I need to restock my hand or wanna mess with my opponents hand
Scuttling Doom Engine : Can deliver a lot of damage quickly - swing for 6 (possible unblockable) damage and dish out another 6 when he dies
Molten Primordial : awsome in multiplayer or when you need to take over one big threath from your opponent. Bazaar Trader makes the thread you took over yours permanently - or you can sack it with Barrage of Expendables before you have to return it to your opponent
Spawn of Thraxes : late game this can finish your opponent off just by entering the battlefield. Also a great option if your opponent has an effeckt like Stormtide Leviathan on the board
Angel of Despair : Removal - and the only card I can't hardcast.
Perilous Myr : cheap artifact you get on the board quickly so you have something to sack to Goblin Welder and a free 2 damage
Combustible Gearhulk : card drawl or damage (and yes I've drawn the next to cards once when I had to put them into my graveyard - instakill)
It That Betrays : doesn't really need an explanation
Pathrazer of Ulamog : Same as above
Wurmcoil Engine : one of my favorites. He's so versatile - a big threath on his own, gives you lifelink (often needed) and he leaves his 2 little children behind if you sack him
