Cazzeo, thanks for the videos !

I was thinking about

1. e4
2. e5 f6
3. f3 d4 d5

Is it any good ?

After 4.f5 Qg5 Qxc1 Qxd1+, I think it is. 5.Kxd1 d6 dxc7 cxb8Q Qxe5+ seems strong for white.

But 4.d6 Bg4 Bxf3 Bxd1 doesn't get mated, and these types of lines tend to work out well for black. (It's like he's flipped colors).

5.Kxd1 Bg5 Bxf6 Bxd8 <some move> is probably the best try. Black threatens mates on f1, and Nf3/Nh3 run into 6.g5 g4 gxh3 hxg2 gxh1Q Qxf1+, which amazingly doesn't seem to get mated. So maybe king has to move, and you'd have to evaluate from there.

What about

5.Kxd1 Bg5 Bxf6 Bxd8 Bb5+ leaving Black with only 5 moves to mate, since he has to deal with the check first ? Am I missing a mate ?

Yeah, that looks like a real try. Maybe 6.Kxd8 a6 axb5 Rxa2 Rxa1 Nh6.

White has a lot of series to play Rxa1 and Ng1xh8, though... would have to go through all of them.

Hmmm, looking back at the four, 4.Ne7 Nxd5 Nc3 Nxd1 seems like the best. d6 blocked in the bishop in the other series, and the advanced d5 pawn was annoying. This series gets rid of it and the queen.

5. Kxd1 Bg5 Bxf6 Bxd8 Bxc7 ? White does have a knight and Black will have to move the d-pawn first to activate the bishop on c8.

Gets mated to Re1 , but 4.Ne7 Nxd5 Nc3 Nxd1 5.Kxd1 Bg5 Bxf6 Bxd8 Kd2 is the critical try, and not sure what's going on. This might be good for white.

4.d6 Bg4 Bxf3 Bxd1 5.Kxd1 Bxg5 Bxf6 Bxd8 Bb5+ 6.Kxd8 a6 axb5 Rxa2 Rxa1 Nh6 is our other critical line.
and
4.f5 Qg5 Qxc1 Qxd1+ 5.Kxd1 d6 dxc7 cxb8Q+ Qe5+, which I haven't verified actually loses for black.

Like, for example:

4.f5 Qg5 Qxc1 Qxd1+
5.Kxd1 d6 dxc7 cxb8Q Qxe5+
6.Kf7 Bd6 Bxe5 Bxb2 Bxa1 g6

Hmm, this looks strong for black... since Ke2 Bb5xd7xc8xb7xa8-d5+ gets mated on e1... White might have something, though, complicated like all e5 f6 lines.

Ah yes, I missed that. So one would have to analyse the position after Kd2.


7. g4 g5 gxh6 hxg7 gxh8Q + 2 spare moves ?

Can't leave the rook on a1... white would get mauled... either mated or, if he moves king off back rank, Rxteam.

Might have spoken too soon. 7.Ne2 g4 g5 gxh6 hxg7 gxh8Q Qxf8+. Can't find a mate.