I'm pretty sure the winner (wish there could be more than one) will just be put on SGS, but I would sincerely like to see these earnable in-game. Jagex probably won't read this or care, but here are some ideas:
PANDA: If the player ever gets to visit the Eastern Lands. Or, a special reward from player-owned ports.
PEACOCK: Elf city quest!!! Simple and awesome.
DUNGEONEERAM: A reward bought by tokens. The art looks super complex and detailed, so it's probably worth a high-level reward, like being unlockable at level 120. But then we probably wouldn't see it in-game too much, but oh well, more motivation to train.
MECHA BIRD: Meh the dwarven questline is over and I'm sure there are no plans for a new one in a long long while. I suppose you might as well put it on the SGS (it even says so on the artwork lol). It only has 4% votes anyway.
SPRITE: If a divination minigame or D&D is ever released...
PUDDING: Lol this one is so random. A hiscores reward or something I guess?
Either way the entries look great. I voted for the peacock c:
01-May-2014 02:22:08