Is Screaming Swarm legal in Standard, Modern, and Commander?

Screaming Swarm is legal in: Modern, Pioneer, Legacy, Vintage, Commander, Historic.

Screaming Swarm

Q: What type of card is Screaming Swarm?

Screaming Swarm is a Creature — Bird Horror. Its oracle text reads: "Flying Whenever you attack with one or more creatures, target player mills that many cards. (To mill a card, a player puts the top card of their library into their graveyard.) {2}{U}: Put this card from your graveyard into your library second from the top."

Creature — Bird Horror

Flying

Whenever you attack with one or more creatures, target player mills that many cards. (To mill a card, a player puts the top card of their library into their graveyard.)

: Put this card from your graveyard into your library second from the top.