Anytime an opponent casts any spell, you amass Orcs for 1, constantly giving you a creature to sacrifice or a massive one to attack with
EDHREC users are doing this by playing Rev in decks led Will, Scion of PeaceWill, Scion of Peace, which helps you cast all the cards you drew, and The ArchimandriteThe Archimandrite, which lets you threaten a lethal attack out of nowhere
Isshin decks typically combine token generators like Adeline, Resplendent Cathar with burn effects like Hellrider and Purphoros, God of the Forge to blitz the table to 0 before they can react
Narratively, it introduced the city itself, and four of its Guilds, a monumental task that it carried off with aplomb
These cards are pretty powerful, so Im not terribly surprised