So noticed a new upcoming game, Artwhirl.

I had checked both Nutaku and Johren; they both have it, of course, but for some reason Johren seems more/better -- aka, it says you get extra rewards for # of pre-reg and retweets, plus it has a pre-roll for starter.
Note: Not sure if you'll actually get the extra bonuses, since there was no twitter link, but I did find one when googling it -- with only 20-ish RT, so dunno.