411 REFERENCE · Wikibooks
Chess Opening Theory/1. g4/1...d5/2. Bg2
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
2. Bg2
Grob's Gambit
White fianchettos the bishop, gambiting the pawn on g4 as there's no actual way to defend it. In exchange they have a few tricks up their sleeve. Black usually accepts the gambit by taking the free pawn with /2...Bxg4/.