Is Ossuary Rats legal in Standard, Modern, and Commander?

Ossuary Rats is legal in: Legacy, Vintage, Commander, Pauper.

Ossuary Rats

Q: What type of card is Ossuary Rats?

Ossuary Rats is a Creature — Rat. Its oracle text reads: "When this creature enters, it deals X damage to target creature or planeswalker an opponent controls, where X is the number of creature cards in your graveyard."

Creature — Rat

When this creature enters, it deals X damage to target creature or planeswalker an opponent controls, where X is the number of creature cards in your graveyard.

Set Jumpstart 2022

Rarity Common

Mana Value 6

Artist Ralph Horsley

Collector # 24

Scryfall Gatherer