Is Callidus Assassin legal in Standard, Modern, and Commander?

Callidus Assassin is legal in: Legacy, Vintage, Commander.

Callidus Assassin

Q: What type of card is Callidus Assassin?

Callidus Assassin is a Creature — Human Shapeshifter Assassin. Its oracle text reads: "Flash Polymorphine — You may have this creature enter tapped as a copy of any creature on the battlefield, except it has "When this creature enters, destroy up to one other target creature with the same name as this creature." Power/Toughness: 3/3"

Creature — Human Shapeshifter Assassin

Flash

Polymorphine — You may have this creature enter tapped as a copy of any creature on the battlefield, except it has "When this creature enters, destroy up to one other target creature with the same name as this creature."

Power/Toughness: 3/3

Set Warhammer 40,000 Commander

Rarity Rare

Mana Value 6

Artist Bryan Sola

Collector # 109

Scryfall