There are multiple ways to earn more free packs, and youll get some simply by playing the game
Later in the game, you can pay two black and two red, as well as exile five other cards from your graveyard, in order to bring Kroxa back onto the battlefield and force your opponent to discard again
Getting value from triggers is great, but getting double helpings is even better
Usually, Standard is a format where there aren't many modifiers like cantrips or MDFCs, so these numbers won't vary as much across seasons
The deck then features a ton of different instants and sorceries to trigger these abilities including spells that create creature tokens, bounce effects, draw spells, direct damage/removal, etc
Dragonspeaker Shaman helps get them out at a more reasonable rate so your opponents cant overwhelm you