magic how does this weird card work

[SlowFast]

how does this card work in magic:

Hanna (Vanguard) - Gatherer - Magic: The Gathering

[Arix]

It's a Vanguard card. Vanguard is an alternate format, like Planechase and Archenemy. In the format, each player takes a Vanguard card, which changes some things about the game. For example, if your card is Hanna, you start with 15 life instead of 20, 8 cards instead of 7, and throughout the game, all your spells cost 1 less to cast.