Is Precipitous Drop legal in Standard, Modern, and Commander?

Precipitous Drop is legal in: Modern, Pioneer, Legacy, Vintage, Commander, Pauper.

Precipitous Drop

Q: What type of card is Precipitous Drop?

Precipitous Drop is an Enchantment — Aura. Its oracle text reads: "Enchant creature When this Aura enters, venture into the dungeon. (Enter the first room or advance to the next room.) Enchanted creature gets -2/-2. It gets -5/-5 instead as long as you've completed a dungeon."