Now that Alara Reborn is finally (pre)released, I don't feel the need to show only multicolor cards any more (or to color critique every card I show). This is the last one. Starting tomorrow, there'll be a new theme week. It will be just like Land Week except without any land.
Power/toughness tied to number of something - All colors. Frequently tied to that something's main color. For hydras, that's red (although green is secondary).
Token generation - All colors. Most common in green, then white, then black and red (about even), then blue.
Card drawing - Blue, then green.
Sacrificing things to draw cards - All colors, but particularly green/blue/black.
Brood Hydra should probably just be green, but blue is excusable.
Driven to Greatness
2 months ago