Search your library for up to that many land cards, put them onto the battlefield tapped, then shuffle
While I'm sure there will be plenty of naysayers because the tribe doesn't have a ton of support in Magic 's history (especially considering one of the handful of rare Horses in Magic is Akroan Horse, which Donates itself to the opponent when it enters the battlefield), it's technically possible to build horse tribal
Not only do you have a League Card, but so too does every trainer in-game, from gym leaders to general trains and even your dear friend Hop
The most recent of these is one that you are probably all familiar with and that was Sword and Shield Crown Zenith
Decks Included: Quick Draw
The granted abilities effectively use "this permanent" rather than "[that card's name]," so you treat the abilities as though they were printed on the creature that gained the ability