When a deck is designed to amass an army of devastating Demons, assembling a group of four Demons at once is a rather easy feat to achieve, especially when you have access to mana cost reducers like Heartless Summoning and Herald of Slaanesh.
These cards can turn a game into a non-game, and they do it early
The Invitational champion would submit their initial design, which would then be developed and tweaked like any other card and eventually printed in a Standard-legal set
Keep in mind, even if you're not playing Game Changers in your Zodiark deck, the fact that your commander forces all of your opponents to sacrifice half of their non-God creatures when it enters will not be the sort of game a lot of more casual players will be looking to play, so make sure your pod is happy with difficult mode
Take Commander 2015 as a good example
now, those boxes can be sold for anywhere between $500-600