About this opening
Four Knights Game: Halloween Gambit, Plasma Variation is an opening in the Encyclopedia of Chess Openings,
classified under code C47. ECO group C (C00–C99)
covers open games (1.e4 e5) and the French Defence, including the Ruy Lopez, Italian, Scotch and King's Gambit. This particular variation is reached
after 22 half-moves from the
starting position, with the move sequence 1. e4 e5 2. Nf3 Nc6 3. Nc3 Nf6 4. Nxe5 Nxe5 5. d4 Nc6 6. d5 Ne5 7. f4 Ng6 8. e5 Ng8 9. d6 cxd6 10. exd6 Qf6 11. Nb5 Rb8.
It belongs to the Four Knights Game family.
Within that family this is a level-2 branch (the Halloween Gambit → Plasma Variation line). The immediate parent line is Four Knights Game: Halloween Gambit, transitioned via 11…Rb8.
The opening sequence in prose form: 1.e4 e5, 2.Nf3 Nc6, 3.Nc3 Nf6, 4.Nxe5 Nxe5, 5.d4 Nc6, 6.d5 Ne5. 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.
Use the interactive board above to walk through the moves position-by-position. Click any move in the navigation to step backwards, or use the keyboard arrow keys. For statistical data — how often master-level players have reached this position, White's win-rate, draw frequency, Black's score — see the panel in the right column.
Caissly's coverage of C47 extends through every named sub-variation in this line and across all four locales (English, Spanish, Portuguese, Russian). Where editorial commentary exists for a specific variation it appears as the page body; otherwise the page presents the structural data, board, and statistics as shown here.