Editing Checkmate (section)

===Two and three knights===
;Two knights
{{Main|Two knights endgame}}
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|Checkmate positions are possible to construct, but they cannot be forced.
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|Checkmate cannot be forced. Here, ...Ka8?? allows checkmate (Nbc7#), but ...Kc8 avoids it.
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|White cannot force checkmate because of stalemate.
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It is impossible to ''force'' checkmate with a king and two knights, although checkmate positions are possible (see the first diagram). In the second diagram, if Black plays 1...Ka8{{chesspunc|??}} White can checkmate with 2.Nbc7#, but Black can play 1...Kc8 and escape the threat. The defender's task is easy – they simply have to avoid moving into a position in which they can be checkmated on the next move, and they always have another move available in such situations.<ref>{{harvnb|Speelman|Tisdall|Wade|1993|p=11}}</ref>

In the third diagram, one knight is guarding c1, leaving the other knight to try to checkmate. After 1.Ndc3+ Ka1, White needs to get the knight on e2 to c2. But if White plays 2.Nd4, Black is [[stalemate]]d.<ref name=pand09p59>{{harvnb|Pandolfini|2009|p=59}}</ref>

Under some circumstances, two knights and a king can force checkmate against a king and pawn (or rarely more pawns). The winning plan, quite difficult to execute in practice, is to blockade the enemy pawn(s) with one of the knights, maneuver the enemy king into a stalemated position, then bring the other knight over to checkmate.<ref name=pand09p59 /> (See [[Two knights endgame]].)

;Three knights
{| style="float:right;"
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| [[File:Chess kll45.svg]]
| [[File:Chess nll45.svg]]
| [[File:Chess nll45.svg]]
| [[File:Chess nll45.svg]]
| [[File:Chess kdl45.svg]]
|}
Three knights and a king can force checkmate against a lone king within twenty moves (assuming that the lone king cannot quickly win a knight).<ref>{{harvnb|Fine|1941|pp=5–6}}</ref>  These situations are generally only seen in [[chess problems]], since at least one of the knights must be a [[promotion (chess)|promoted piece]], and there is rarely a reason to promote a pawn to a piece other than a queen (see [[underpromotion]]).