unknown variation
nope if g3 nxe4 winning the knight back or a rook
It's called the "Busch-Gass Gambit". It looks pretty dubious to me.
I think I prefer 5.g3 Qxe4 6.Nf3 because it doesn't block the development of your kingside pieces, planning 7.Qe2, 7.Nc3, or 7.Bg2 to take advantage of Black's poor queen position. After a queen swap White's position is easy to play.
erikido23- After 5. g3 Qxe4, 6. Nf3 blocks the queen's attack on the rook and saves both pieces! set it up on a chess board and play it out.