Is Persistent Marshstalker legal in Standard, Modern, and Commander?

Persistent Marshstalker is legal in: Standard, Modern, Pioneer, Legacy, Vintage, Commander, Historic.

Persistent Marshstalker

Q: What type of card is Persistent Marshstalker?

Persistent Marshstalker is a Creature — Rat Berserker. Its oracle text reads: "This creature gets +1/+0 for each other Rat you control. Threshold — Whenever you attack with one or more Rats, if there are seven or more cards in your graveyard, you may pay {2}{B}. If you do, return this card from your graveyard to the battlefield tapped and attacking."

Creature — Rat Berserker

This creature gets +1/+0 for each other Rat you control.

Threshold — Whenever you attack with one or more Rats, if there are seven or more cards in your graveyard, you may pay . If you do, return this card from your graveyard to the battlefield tapped and attacking.