Hmm, interesting. Initially I thought this would be a terrible meta, until I read the part about the 8/12/24/30, and now I'm thinking it'll be a lot more interesting; without that, one deck was standing out to me as being the obvious dominator. It's also at a very good time for me, which is odd, because the first time I saw this thread I'd have sworn it said it was at 4am for me, but it's 4pm :p
Also, is it legal to use any deck mark? People might conceivably want to use a water mark for forest spirit or a gravity mark for scarabs or air mark for pegasus.