Lizard Defense, Mittenberger Gambit

The Mittenberger Gambit departs from the usual 3...d6 of the Modern Defense main line. Instead of letting White keep the e4-d4 duo and undermining it slowly, Black challenges e4 immediately with 3...d5. The d5-pawn is attacked by both the e4-pawn and the c3-knight and has no defender, so Black is effectively offering a pawn in return for open lines for the g7-bishop and fast development. Engines prefer to take it, with 4. Nxd5 and 4. exd5 their top choices, and rate the position as a slight edge for White.

In practice the most frequent reply is 4. e5, which declines the pawn and gains space, producing a closed center in which the advanced e-pawn blocks the long diagonal and Black must look for counterplay with pawn breaks rather than piece pressure. Accepting with 4. exd5 is the second most common choice and gives White somewhat better results than Black. 4. Be3, reinforcing d4, is a quieter way to decline. The line is a rarely seen sideline, and overall results on Lichess are evenly split between White and Black.