Is Mine Security legal in Standard, Modern, and Commander?

Mine Security is legal in: Historic.

Mine Security

Q: What type of card is Mine Security?

Mine Security is a Creature — Kavu Soldier. Its oracle text reads: "Trample When this creature enters, conjure a card named Flametongue Kavu into the top eight cards of your library at random. It perpetually gains "You may pay {0} rather than pay this spell's mana cost." Power/Toughness: 3/1"

Creature — Kavu Soldier

Trample

When this creature enters, conjure a card named Flametongue Kavu into the top eight cards of your library at random. It perpetually gains "You may pay rather than pay this spell's mana cost."