Is Mardu Shadowspear legal in Standard, Modern, and Commander?

Mardu Shadowspear is legal in: Modern, Pioneer, Legacy, Vintage, Commander.

What type of card is Mardu Shadowspear?

Mardu Shadowspear is a Creature — Human Warrior. Its oracle text reads: "Whenever this creature attacks, each opponent loses 1 life. Dash {1}{B} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)"

Mardu Shadowspear

Creature — Human Warrior

Whenever this creature attacks, each opponent loses 1 life.

Dash (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)