About this opening
Rat Defense: Petruccioli Attack is an opening in the Encyclopedia of Chess Openings,
classified under code B00. ECO group B (B00–B99)
covers semi-open games (1.e4 with Black playing anything other than 1…e5), with the Sicilian, French, Caro-Kann and Pirc/Modern at its heart. This particular variation is reached
after 3 half-moves from the
starting position, with the move sequence 1. e4 d6 2. h4.
The opening sequence in prose form: 1.e4 d6, 2.h4. From this position the encyclopaedia records no further canonical continuations — practical play branches into unnamed transpositions or returns to the parent line for alternative ideas.