Is Argivian Phalanx legal in Standard, Modern, and Commander?

Argivian Phalanx is legal in: Modern, Pioneer, Legacy, Vintage, Commander, Pauper, Historic.

Argivian Phalanx

Q: What type of card is Argivian Phalanx?

Argivian Phalanx is a Creature — Human Kor Soldier. Its oracle text reads: "Affinity for creatures (This spell costs {1} less to cast for each creature you control.) Vigilance (Attacking doesn't cause this creature to tap.) *New Argive welcomed the kor people when they were displaced by the Rathi overlay. The kor repay that kindness with fierce loyalty.* Power/Toughness: 4/4"