Jeskai (URW) merges Blue, Red, and White around spell-based strategies
My particular favourite is Yunas Whistle a heartbreaking moment in the game meant to help Tidus find her again even over great distances, but here its used to call a creature from your deck, making you search for it until you hit one and actually being able to call it forth unlike poor Tidus in game Listen to my story The Commander format already lends itself well to the FF setting being a multiplayer version of the game so it feels a lot like forming a party with an unlikely band of heroes and dealing with some particularly vicious villains
Gaining life with Bilbo lets you gain one extra point of life, which is vital for using his main ability
His casting cost is only 1 colored mana, and generating a ton of colorless mana often isn't very hard, so this could be a way to turbo something out that you really want
The same is true for replacement effects that apply to it, such as entering with one or more +1/+1 counters (such as the effect of Slinza's second ability, not coincidentally) or entering as a copy of another creature
Of note, every color except blue is represented in the decks