Problem is competitions like this one and cards like Flying Weapon. It's unfair if everyone can use it because it makes Air weaker compared to others. It also enables you to take all kinds of different pillars and zero cost cards so that you might have cards from all 12 elements, yet your deck would be called a mono-deck.
This rule should be amended to allow Pillars of other types in. There's just no way in the frozen depths of Watery Hell that I can effectively use Physalia, Toadfsh, or Trident based on one quanta per turn from a Mark. That decision utterly cripples my ability to field a poison, denial, or infection-based deck, and I KNOW that other Masters are feeling the same way. (Furthermore, I certainly can't hope to use both Physalia and Toadfish in the same deck, which I was planning on doing.)
Even my opponent Kamietsu cannot hope to make a decent Lava Golem deck with just a Mark of Earth at his disposal. Only Aether and Light -- and to a lesser but reasonable extent, Death and Entropy -- are happy to play with just a Mark of off-element-ness.
That's an unfair advantage to those few Masters. I'm all about not allowing Animate Weapon and other actual cards into mono-decks, but disallowing pillars really hurts some elements a lot more than others.
Amd as for my anti-Fire deck, I think I'll go permanentless to make all of his Explosions useless, and pack 6 Ice Bolts -- Fire creatures are uniquely fragile -- and a few Mind Flayers so that I don't have to waste Ice Bolts on the Fire Spirits and Lava Golems.
Of course, having said that, I can count on a deck built without any Fire Spirits and Lava Golems, which means that my Ice Bolts will be even more effective on his main offense -- the Crimson Dragons.
Which means no Explosions or big creatures of any kind. Ah-hA!!! He's going to play a Firebolt/Fahrenheit deck!
I'd better play a quick creature stompy to beat him down before he builds up enough Quanta to kill me!
Umm...Fire has ways of murdering quick creature stompys.
Wait, no! Tridents! I have those! I can deny his Quanta, and his Fahrenheits will be powerless...but he's packing Explosions. But I said I was coming with no permanents, so he won't. But....
What if he uses Cremation?!?
/me 's head explodes.