Build up a strong enough board presence, or get your opponent low enough with chip damage, and you can create a game state where your opponent can't even kill your creatures without risking death themselves
The Brave Little Tailor card made up most of the sales, despite not being exclusive to the set
Self-Destruct While I'm not sure how many copies you want of this card, I am pretty scared of it due to its interaction with Heartfire Hero and Screaming Nemesis
One final thing to note is that if you use any of these legends as your commander (or Otrimi, the Ever-Playful, a sixth legendary mutator printed in the upcoming Commander precons), then any mutated creature with the commander on top will deal commander damage
You'll also probably want to run some birds with flying, so it is easier for you to attack and activate Choco, Seeker of Paradie's ability
These characters hail from Final Fantasy IX, which we havent seen any cards from so far, so this would make a lot of sense