Okay, boys first XD Some of them have been here before (actually, most have, I think XD)
Misery is looking for a Mystic mare, but he's going to be extremely picky. Not likely that he'll find his dream girl XD
Whip's also looking for a Mystic mare, probably not fire based though. Fire and tropical jungle don't quite get along XD Preferably with horns or spiky bits, but not 100% required. All his other mares have them though!
Charge is looking for an animal mimic mare. Pretty much any mimic mare XD His song is located in the jungle/savannah.
Mysterious Rhythms is looking for combo species mares. That's pretty much his only requirement. Mares that look nice with him and his current two are also good.
Flame's Embrace, I'm not too sure what he wants, haha. Something that goes well with his song?
Hallowed Earth is looking for long-lined mares. Preferably ones that can trace back to the earlier Songs of the Rainbow, but long-lined Mystics are also acceptable. He's a snob.
Prickle is, well, prickly. I'm not sure if he really wants to have a song, but winter/holiday themed mares are welcome. Ones that can withstand his prickly nature are good. He's got a soft heart, but shows a cranky face. Warmth is working on him!