Here's an interesting idea. I started with a manabase, and then decided to try to build a deck around it there.
So, here's the general idea of the mana base. You've got tons of changelings. What best way to play lands than something like...
// Lands
4 [SHM] Reflecting Pool
4 [MOR] Murmuring Bosk
4 [LRW] Gilt-Leaf Palace
4 [MOR] Primal Beyond
4 [EVE] Fetid Heath
4 [SHM] Wooded Bastion
That? Here we've got tons of G/B/W with changelings making it easy for us to get the lands hitting untapped. Oh, and don't worry, we've got some mana making crits in case we need 'em.
// Creatures
4 [EVE] Bloom Tender
4 [MOR] Chameleon Colossus
4 [MOR] Scarblade Elite
4 [LRW] Changeling Titan
4 [LRW] Changeling Hero
4 [SHM] Kitchen Finks
4 [SHM] Murderous Redcap
4 [SHM] Cemetary Puca
// Spells
4 [LRW] Nameless Inversion
So, you've got PLENTY of removal here. Scarblade Elite, Murderous Redcap, and, of course, Nameless Inversion. Voila, their crits are toasted. Then, your Cemetary Puca is a nice finisher, if you pull off a combo with a Scarblade, or, of course, there's always pummel with Titan/Hero. Kitchen Finks is a nice card to stick in any deck running G/W with its EASY 4 life gain and ability to stand in the way of a couple crits.
Any thoughts?