@Whoami: As far as I know, you don't choose your magical aspects-y stuffs. Mancala gives you stuff based on your stats and history and whatever. And, not to be a killjoy (I'd hate to be a fun-wrecker), but I think Boggle already has the Blood-magic type of power? But maybe there's more than one type?

All that said, maybe you could PM Mancala and see if you can work something out? Just have a nice chat with him about it and figure things out. He seems like a nice and reasonable guy from what I've seen. He's probably willing to accommodate new ideas. I'm sure you can figure something out. ^-^