While there's always a primary color, there's not always a secondary or tertiary color
This is especially true if youre playing a deck loaded up with creatures and other permanents with Enter the Battlefield abilities, as any targeted effect your opponent tries to use on your permanents is likely to let you rebuy an Enter the Battlefield
This makes it easier for you to cast big spells and pairs well with any mana sinks or X spells
Maralen of the Mornsong and Colfenors Plans are two just such cards that I happened upon way back in early 2008, the sets at the time in Standard were: Tenth Edition, Coldsnap, Time Spiral, Planar Chaos, Futuresight, Lorwyn, and Morningtide very cool sets that collectively had a metric butt-load of awesome cards, like Tarmogoyf, Mutavault, and Vendilion Clique
This relatively unknown slang can have huge effects on certain formats (a hint, its not Commander)
Making Squirrels on entry and attack is solid, and being in green lets her access the token doublers that Krenko missed out on
