I'd play Bxh3... if gxh3 Qxh3 and now White has to find f2-f3, or f2-e4, to survive (if my analysis is correct, which is a bit of a stretch) -- even after f3, I think Black has compensation for the piece -- two pawns and a very exposed enemy king.
Marshall attack ruy lopez people; query.

You pretty much have to play 14...Bxh3 15. gxh3 Qxh3. Also, white has to find 16. Re5 Bxe5 17. dxe5 as both f3 and f4 fail. 16. f3 fails to Qh2+ followed by Bg3+, and 16. f4 fails to 16...Nxf4 17. Bxf4 Bxf4 with the same idea of Qh2+ coming.
After Re5 how about f6? Be nice to win the Rook outright. *edit*(f6 no good, he has Rh5) I think the sac's good!
As for f3 Qh2 followed by Bg3+ ... I looked at that extensively and yeah black pushes white all around but i couldn't find the death blow. Also... "f4 fails to 16...Nxf4 17. Bxf4 Bxf4 with the same idea of Qh2+ coming"... I don't think Qh2+ is all that ... after 18 Qe2 Qh2+ doesn't accomplish anything... How does Black continue the attack? Qg3+ gives a perpetual, but i think white's very happy to draw. How about 18.Bh2+! kh1 (Kf2? Qg3+ Kf1 Qg1#) Bg3+ Kg1 Bxe1 Qxe1 Re8 -+
yeah, f4 is crap... I still want to see f3 descisively refuted, I suspect it can be.

f3 has been decisively refuted. If 16. f3, then 16...Qh2+ 17. Kf1 Bg3 wins a rook or mates. 16. Re5 Bxe5 17. dxe5 is not so clear. I'll see what Fritz 8 thinks of this tomorrow morning.

f3 has been decisively refuted. If 16. f3, then 16...Qh2+ 17. Kf1 Bg3 wins a rook or mates. 16. Re5 Bxe5 17. dxe5 is not so clear. I'll see what Fritz 8 thinks of this tomorrow morning.
... yeah, f2 Qh2+ Kf1 Bg3 is crushing... that leaves Re5. I put this to my engine, Fire, and it sees Bxh2 gxh2 Qxh2 Re5 as the continuation (f4 was the second best defense, but at -5.00, obviously completely lost), with Black holding a definite plus. Indeed in a quick engine v engine test, Black wins.
Some people play this move. I wanted to know if this was a mistake and , if so, why and how can I punish it?