Is Great Defender legal in Standard, Modern, and Commander?

Great Defender is legal in: Legacy, Vintage, Commander.

What type of card is Great Defender?

Great Defender is an Instant. Its oracle text reads: "Target creature gets +0/+X until end of turn, where X is its mana value."

Instant

Target creature gets +0/+X until end of turn, where X is its mana value.

Set Legends

Rarity Uncommon

Artist Mark Poole

Instant Commander Legacy Vintage