2959c81e_ufficient_Mating_Material_Rule__2
[0] Example J [2] 
Black to move. This is just an example to show how important is to recognize incoming stalemate in time. This position is drawn according to the rule, right after white had moved Qg4+. There is only one move sequence in this position and it leads to stalemate. Therefore the game is drawn, since none of the players can mate each other. If the game hadn't ended in draw as the rule says, the move sequence would be Rxg4+, Rxg4+, Qxg4+ then Nxg4, when it would be stalemate. It's impossible to avoid stalemate, so the game can't end in mate. Therefore this position also matches the rule, so the game is immediately drawn after Qg4+.
[E4EC] The insufficient Mating Material Rule
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