mtg leyline cards of Mutation (188) : Toys & Games add an additional G Leyline of Permanence : r/custommagic

Mondo Gecko | 1 Colorless Mana, 2 Blue Mana Legendary Creature Lizard Mutant 1 Colorless Mana, Discard a card: Until end of turn, Mondo Gecko becomes the color of your choice and gains hexproof from that color

And since you can supplement this "as long as mana lasts" part with its own ability, it can be called a typical "win if not removed" type of commander

If you combine both you can easily kill a player with regular or Commander damage

Lastly, at the time of this writing, Card Kingdom has paused collection purchases

Otherwise, meet back here for the same thing at the end of next year

In part, that depends on which card you put on top