As a young troll, Boomer loved to blow things up - particularly sheep.  Later, he was drafted into the troll army, where they gave him LOTS of things to blow up.  However, Boomer realized the sole mission of the army was war and conquest.  Even though he was a troll, these things didn't interest him.  So he left the trolls after saving a town from being destroyed by them.  Not long after, he was invited to be a Skylander - the only troll ever to win such an honor.  Now he uses his explosive skills to fight evil... much to the relief of sheep everywhere.