[quote=Raineh Daze]
The reason for UBW is White, his underlying personality is a mix of Red and Black, and actions in Archer's past throw Green into there. Blue gets in because of how he acts. Focusing on the end result trivialises the issue.Plus the 'recreate every weapon' part of UBW fills it with a panoply of weaponry embodying every colour. >.>
[/quote]

Everyone has a bit of every color, but one's current behavior and philosophy are generally what dictate their colors. See: Planeswalkers that have been different colors.

Blue = Artifacts fo sho though. A spell that summoned craploads of swords would be hella Blue. Reminder that colored artifacts were introduced as the gimmick of the Primary-Blue shard of Alara.