A poll is fine - It's easy to catch people cheating.
This also isn't just for people playing the respective games.
Some of these designs are very appealing even if you have never heard of one of the titles, so it would be an easy thing to share with family/friends/whoever.
Don't you need a forum account to vote on a forum poll, though? I think the Ragnarok ones overall will be favoured because they have player bases triple (possibly even more, guesstimating) the size. Then again, I suppose it's true the largest game will probably sell the most shirts. That makes it kind of tricky. I hope we see a fair opportunity for other games to receive a prize.
Ultimately it doesn't really matter to me as I'm not participating, just speaking out what I know a lot of people are thinking. Hopefully it turns out for the best!
Edited by ceinchase, 20 August 2015 - 06:59 PM.