Hi!
Today a deck I'm quite excited about, which (ab)use buyback.
The principle is simple : get tons of mana, get buyback free, and cast spells again and again.
The challenge is was to have something reliable with four colours. It went through a lot of adjustments, and I think it still needs more. White and blue are much less prominent than black and red. Let's see why.
There are several ways to use this deck. But the first thing you want, is to survive the early game, while the precise mechanic of the deck is taking shape.
For that, cast one or two God-Pharaoh's Faithful early. They are decent blocker and will give you some early life gain.
Once you're kinda safe, the most important card of the deck for cheap buybackers at this step is Memory Crystal. Get at least 2 of them on the field, with the help of Mystic Speculation. Then cast a couple of Sentinel Tower.
Now what to do?
You can either go black, with an early Urborg, Tomb of Yawgmoth and Liliana of the Dark Realms. Use her to fetch more Swamps, and pump her with Clockspinning. The aim is to get her emblem, which combo well with Urborg, and get an army of Lab Rats, or board sweep with Evincar's Justice (while doing tons of damage from the Towers, and getting life from the Faithuls).
But the most intersting and reliable way is to go red, with early Runaway Steam-Kin and Guttersnipe. Long story short : Steam-Kin + Searing Touch + 2 Memory Crystal = infinite damage combo.
Yes, if the Steam-Kin has 3 counters on it, you get 3 red mana, cast the Touch thrice, which gives 3 counters on the Steam-Kin and so on (while doing tons of damage from the Towers, and getting life from the Faithuls).
Any suggestions?