You may vote once per day. This is an honor system, and we are all honorable gamers; please do not abuse it. If this means you vote once at night one day, and once the next morning - that's fine, but don't vote again until the following day.
Grouped young, adult, ancient and Wyrmlings together so there are only 15 total. For Fiends, I'll probably split into Demons, Devils and Other, though I'm tempted to let it just be a huge Blood War and make downvotes worth 3 or 4 to speed it up.