Is Grenzo, Dungeon Warden legal in Standard, Modern, and Commander?

Grenzo, Dungeon Warden is legal in: Legacy, Vintage, Commander.

What type of card is Grenzo, Dungeon Warden?

Grenzo, Dungeon Warden is a Legendary Creature — Goblin Rogue. Its oracle text reads: "Grenzo enters with X +1/+1 counters on it. {2}: Put the bottom card of your library into your graveyard. If it's a creature card with power less than or equal to Grenzo's power, put it onto the battlefield."

Grenzo, Dungeon Warden

Legendary Creature — Goblin Rogue

Grenzo enters with X +1/+1 counters on it.

: Put the bottom card of your library into your graveyard. If it's a creature card with power less than or equal to Grenzo's power, put it onto the battlefield.