WHITE.BLACK.
1.P to K 41.P to K 4
2.P to K B 42.P takes P
3.Kt to K B 33.P to K Kt 4
4.P to K R 44.P to Kt 5
5.Kt to K 55.B to Kt 2

Black has various defences here, the best being the text-move and 5. ... Kt to K B 3.

6.P to Q 4...

If 6. Kt takes Kt P, Black replies 6. ... P to Q 4; 7. Kt to B 2, Kt to K 2; 8. P takes P, Castles; 9. B to K 2, Kt to B 4, with the better game.

...6.Kt to K B 3
7.Kt to Q B 37.P to Q 3
8.Kt to Q 38.Kt to R 4
9.Kt takes P9.Kt to Kt 6
10.R to R 210.Castles
11.Q to Q 311.Kt takes B
12.K takes Kt12.Kt to B 3

And Black has a good game.

THE ALLGAIER GAMBIT.

Here, as in the Muzio, a piece is sacrificed for an early and strong attack. The opening moves are—

WHITE.BLACK.
1.P to K 41.P to K 4
2.P to K B 42.P takes P
3.Kt to K B 33.P to K Kt 4
4.P to K R 44.P to Kt 5
5.Kt to Kt 5...

This move involves the sacrifice of the Knight, and constitutes the Allgaier.