Is Fuel Tank Feaster legal in Standard, Modern, and Commander?

Fuel Tank Feaster is legal in: Historic.

Fuel Tank Feaster

Q: What type of card is Fuel Tank Feaster?

Fuel Tank Feaster is a Creature — Ooze Druid. Its oracle text reads: "At the beginning of your first main phase, a random creature card with the greatest mana value among creature cards in your hand perpetually gains "This spell costs {1} less to cast." {T}: Add one mana of any color. Power/Toughness: 1/3"

Creature — Ooze Druid

At the beginning of your first main phase, a random creature card with the greatest mana value among creature cards in your hand perpetually gains "This spell costs less to cast."

: Add one mana of any color.