Is Breathstealer legal in Standard, Modern, and Commander?

Breathstealer is legal in: Legacy, Vintage, Commander, Pauper.

What type of card is Breathstealer?

Breathstealer is a Creature — Nightstalker. Its oracle text reads: "{B}: Breathstealer gets +1/-1 until end of turn."

Creature — Nightstalker

: Breathstealer gets +1/-1 until end of turn.

Set Mirage

Rarity Common

Artist Cliff Nielsen

Creature Commander Pauper Legacy