Is Reef Worm legal in Standard, Modern, and Commander?

Reef Worm is legal in: Modern, Legacy, Vintage, Commander, Historic.

Reef Worm

Q: What type of card is Reef Worm?

Reef Worm is a Creature — Worm. Its oracle text reads: "When this creature dies, create a 3/3 blue Fish creature token with "When this token dies, create a 6/6 blue Whale creature token with 'When this token dies, create a 9/9 blue Kraken creature token.'""

Creature — Worm

When this creature dies, create a 3/3 blue Fish creature token with "When this token dies, create a 6/6 blue Whale creature token with 'When this token dies, create a 9/9 blue Kraken creature token.'"

Set Modern Horizons 3

Rarity Uncommon

Mana Value 4

Artist Dan Murayama Scott

Collector # 271

Scryfall Gatherer