checkmate with 2 knights?

rai25

rai25

possible?

marvellosity

Given White's last move was Nb6#, what was Black's last move?

His king must have come from either a7, b7, or b8 - but all these squares are covered. Therefore the position isn't possible.

Tyzer

White to move? That's a bit odd.

 

In any case, this position isn't reachable unless Black is being highly cooperative and/or a total idiot...

 

EDIT: Ninja'd by marvellosity. But what you said isn't quite true - the position can be legally reached, but it requires Black to help.

rai25

so if like that  the black would be so stupid to go to a8

TheGrobe

His king could have come from b8 after being placed in check by the knight on c6.

While possible, the King's option to move to c8 instead of a8 on the previous move, however, is why this position should be drawn.

marvellosity

Good call there, tyzebug.

I guess that's why it's practically impossible to mate with 2 knights. Only one extremely obvious defensive move is required. I think even a rank beginner would intuitively stay out the corner and not get mated.

Tyzer

Yeah. From Wikipedia, "Although there are checkmate positions with two knights against a king, they cannot be forced. The player with the lone king has to make a blunder to be checkmated."

rooperi

Well, in some cases it can be forced, if Black has a pawn

Tyzer

Yep, but only in certain positions. Plus, it's no longer really a two knights mate, but instead a two knights vs pawn mate.

rai25

ok i got it

Tyzer

Taking that bishop gets Black mated faster than any other move though. Only a weak piece-grabber would play that move (or maybe someone who knows you can't force checkmate with two knights, but didn't notice that this position is...special). Then again, in that position Black is lost anyway so it's only a matter of time.

1hitKO
tonydal wrote:

The only feasible reason that I can think of for Black to do that:

 


lol nice

GladysPool

I'm well aware that 2 knights can;t force checkmate against a king. I'm currently playing a game where I have the king v the 2 knights, so my question is why doesn't the chess.com website not allow me to claim the draw. Am I going to have to wait 50 moves before being able to do so?

rooperi

Well, you can blunder into a mate, your draw is a theoretical "book draw". Unlike a single Knight, where mate is impossible, this is an actual insufficient material draw.

nyLsel

If Black has no pawn, then the game is a draw.

nyLsel
GladysPool wrote:

I'm well aware that 2 knights can;t force checkmate against a king. I'm currently playing a game where I have the king v the 2 knights, so my question is why doesn't the chess.com website not allow me to claim the draw. Am I going to have to wait 50 moves before being able to do so?

It can be a book draw or theoretical draw as rooperi said. :D

eddysallin
nyLsel wrote:
GladysPool wrote:

I'm well aware that 2 knights can;t force checkmate against a king. I'm currently playing a game where I have the king v the 2 knights, so my question is why doesn't the chess.com website not allow me to claim the draw. Am I going to have to wait 50 moves before being able to do so?

It can be a book draw or theoretical draw as rooperi said. :D

have u claimed a draw?

GladysPool

I've offered one, but my opponent wants to play on as he's never played with 2 knights before.

SgtDoodles

Tell him you want to experiment, by putting his King in a corner :D