Misère play is the terminal convention in which the player making the last legal move loses. For finite games without draws, this means a player whose turn begins with no legal move wins. The same move rules with the normal-play convention instead make that player lose.
A one-heap removal game makes the difference immediate. If a single object remains and the only move removes it, the player to move loses under misère play and wins under normal play. With two unit heaps in Nim, the first player removes one heap and forces the other player to take the last object, so the position is misère winning even though its normal-play nim-sum is zero.
Changing the terminal condition changes the recursive winning/losing classification. Normal-play formulas, including unrestricted use of Sprague-Grundy theory, therefore cannot be transferred unchanged. Infinite play requires a separate draw or outcome convention.
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