Avatar of Vengeance RRWW

4/3
Whenever you or a permanent you control becomes a target of an opponent's spell or ability, you may pay RW. If you do so, Avatar of Vengeance does 2 damage to target creature or player and you gain 2 life.

Vengeance: blind, blatant and bloody.

Avatar of Decay GGBB

7/7
Flying
Avatar of Decay comes into play with three -1/-1 counters.
Tap, Remove a -1/-1 counter from Avatar of Decay: Each player sacrifices a land.

I imagine Decay to be a wispy female figure with a long rustling gown of skeletal leaves and wings of papyrus.
She is faceless, with only a beaked mask as her visage.
Her left hand is made of spotless, shiny steel, constantly twitching and squeaking - the only sound that she ever makes.

(Yeah I used to be a Magic cards geek =) )