Is Krovikan Rot legal in Standard, Modern, and Commander?

Krovikan Rot is legal in: Modern, Legacy, Vintage, Commander.

Krovikan Rot

Q: What type of card is Krovikan Rot?

Krovikan Rot is an Instant. Its oracle text reads: "Destroy target creature with power 2 or less. Recover {1}{B}{B} (When a creature is put into your graveyard from the battlefield, you may pay {1}{B}{B}. If you do, return this card from your graveyard to your hand. Otherwise, exile this card.)"

Instant

Destroy target creature with power 2 or less.

Recover (When a creature is put into your graveyard from the battlefield, you may pay . If you do, return this card from your graveyard to your hand. Otherwise, exile this card.)