I was actually thinking about this recently while building Monarth's latest version. I'd have to go with two themes based on the situation he's depicted in.
Character reference: Monarth
When he's doing his duties as a dream warden, wandering in the night and going dream to dream, I think this represents some of his mysticality well. But it also depicts the peace he brings to dreams, before vanishing to find the next dream:
When things get battle-oriented, well... The heat is on. Maybe he's the boss or maybe he's just entering battle. Either way:
If you didn't guess already, I love the Legend of Spyro games.