Stanley Variation

The Stanley Variation postpones the f-pawn advance and develops the king's bishop first. With 3. Bc4 the bishop joins the knight on c3 and the pawn on e4 in covering d5, so Black's natural freeing break ...d5 is hard to achieve. The bishop also bears down on f7, and White keeps the option of f4 for later. The position can also arise from the Bishop's Opening after 1. e4 e5 2. Bc4, and some sources classify it there. The engine rates it as roughly balanced. In the Lichess sample White scores slightly better than Black, and draws are rare.

Alekhine recommended the fork trick 3...Nxe4, which removes one of the guards of d5. If 4. Nxe4, then 4...d5 regains the piece and gives Black a broad center. The usual reply is 4. Qh5, threatening mate on f7, and Black almost always answers with 4...Nd6 5. Bb3. Here 5...Be7 (the Monster Declined) 6. Nf3 Nc6 7. Nxe5 is the comparatively calm Alekhine Variation. The alternative 5...Nc6 6. Nb5 g6 7. Qf3 f5 8. Qd5 Qe7 9. Nxc7+ Kd8 10. Nxa8 b6 is the Frankenstein-Dracula Variation, a name coined by Tim Harding. In that line White wins a rook, but Black's king has been displaced to d8 and the game becomes highly complicated. White can steer toward an endgame with 5. Qxe5+ Qe7 6. Qxe7+ Bxe7. After 3...Nxe4, 4. Nf3 is the Boden-Kieseritzky Gambit. In the sample 3...Nxe4 is the only major reply after which Black scores better than White.

Most players choose quieter development. The most frequent reply is 3...Bc5. After it, 4. d3 d6 5. f4 Nc6 6. Nf3 transposes to the King's Gambit Declined, while 4. Nge2 b5 is the Eifel Gambit. The second most common is 3...Nc6, the Three Knights Variation, which can also arise from the Max Lange Defense. It is usually met by 4. d3, the Berlin-Vienna Hybrid, when Black chooses between 4...Na5, 4...Bc5 and 4...Bb4. After 3...Nc6 4. f4 Nxe4 5. Nf3, White plays the Bronstein Gambit.

The Reversed Spanish, 3...Bb4, pins the c3-knight. The sharp 4. f4 Nxe4 5. Qh5 O-O leads to chaotic play that is thought to be level. White can also choose the steadier 4. d3, 4. Nge2 or 4. Nf3. The engine's preferred replies to 3. Bc4 are the three developing moves 3...Nc6, 3...Bc5 and 3...Bb4.