Is Tenacious Underdog legal in Standard, Modern, and Commander?

Tenacious Underdog is legal in: Modern, Pioneer, Legacy, Vintage, Commander, Historic.

Tenacious Underdog

Q: What type of card is Tenacious Underdog?

Tenacious Underdog is a Creature — Human Warrior. Its oracle text reads: "Blitz—{2}{B}{B}, Pay 2 life. (If you cast this spell for its blitz cost, it gains haste and "When this creature dies, draw a card." Sacrifice it at the beginning of the next end step.) You may cast this card from your graveyard using its blitz ability."

Creature — Human Warrior

$0.27 ↗20 similarCommander, Modern

Blitz—, Pay 2 life. (If you cast this spell for its blitz cost, it gains haste and "When this creature dies, draw a card." Sacrifice it at the beginning of the next end step.)