Is Baffling Defenses legal in Standard, Modern, and Commander?

Baffling Defenses is legal in: Historic.

What type of card is Baffling Defenses?

Baffling Defenses is an Instant. Its oracle text reads: "Target creature's base power perpetually becomes 0."

Instant

Target creature's base power perpetually becomes 0.

Set Jumpstart: Historic Horizons

Rarity Common

Mana Value 2

Artist Andrey Kuzinskiy

Collector # 2

Scryfall

Instant