Is The Lord of Pain legal in Standard, Modern, and Commander?

The Lord of Pain is legal in: Legacy, Vintage, Commander.

The Lord of Pain

Q: What type of card is The Lord of Pain?

The Lord of Pain is a Legendary Creature — Human Assassin. Its oracle text reads: "Menace Your opponents can't gain life. Whenever a player casts their first spell each turn, choose another target player. The Lord of Pain deals damage equal to that spell's mana value to the chosen player."

Legendary Creature — Human Assassin

Menace

Your opponents can't gain life.

Whenever a player casts their first spell each turn, choose another target player. The Lord of Pain deals damage equal to that spell's mana value to the chosen player.

Set Duskmourn: House of Horror Commander

Rarity Mythic Rare

Mana Value 5

Artist Greg Staples

Collector # 3

Scryfall Gatherer