Is Referee Squad legal in Standard, Modern, and Commander?

Referee Squad is legal in: Modern, Pioneer, Legacy, Vintage, Commander, Historic.

Referee Squad

Q: What type of card is Referee Squad?

Referee Squad is a Creature — Homunculus. Its oracle text reads: "Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.) Vigilance When this creature enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)"

Creature — Homunculus

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for or one mana of that creature's color.)

Vigilance

When this creature enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Set March of the Machine

Rarity Uncommon

Mana Value 3

Artist Steven Belledin

Collector # 327

Scryfall Gatherer