Is Hardened Berserker legal in Standard, Modern, and Commander?

Hardened Berserker is legal in: Modern, Pioneer, Legacy, Vintage, Commander, Pauper.

Hardened Berserker

Q: What type of card is Hardened Berserker?

Hardened Berserker is a Creature — Human Berserker. Its oracle text reads: "Whenever this creature attacks, the next spell you cast this turn costs {1} less to cast. *"Just let him loose and follow the charge." —Yikaro, Atarka warrior* Power/Toughness: 3/2"