Disclaimer: I will not focus on Art or grammar, unless the latter would make the deck too difficult to understand.

Maverick time then!

It took me a bit to go over the cards and fully grasp the gameplay loop involved with the deck. But after grokking it (I hope), I have to say I like it? Assuming these cards only attack once each, even if they have been to the hand. There's a nice ramping threat level to one of these coming up, hitting something, and then going to The Hand to be replaced by a {Normal} (Then {Weak}) Warrior on the Field. And the more these are played, the more that loop keeps growing, becoming really scary if those {Teamwork} Tokens ramp up too. It's honestly really clever.

For points I'm less sure about, I have to admit hook-wise that the idea of the Grand Melee happening every 25 years got a few blinks from me. Is there a specific reason in your campaign setting it needs to be that long - about a third of a normal human's lifespan? Even Real Life Olympics have just 4-year gap between them. Mechanically, I wonder if some kind of Simple Card Move to help with the gimmick directly is not uncalled for? Difficult to say without testing this in practice, though.

Good job!

The game plan is quite confusing, I don't understand how swapping warriors for cards in hand helps Maverick win. Only one of the power card moves has a benefit related to it, and none of the plans to win do...

A nice simple deck with a neat gimmick. I like it. :)