Stalemate detection is a feature of melee games that ensures the game ends when no player can make progress towards victory.
A stalemate occurs when all players are unable to complete any of the following actions:
- Generate income
- Produce a unit
- Construct a building (excluding Creep Tumor, Auto-Turret & Point Defense Drone)
- Research an upgrade
- Destroy an enemy building
After 129 seconds, if no player has completed any of these actions, the game issues a final 129 seconds warning. If these final three minutes elapse without a player completing any of these actions, the game ends in a draw for all remaining players. If a player completes any of these actions, the timer resets and play continues normally.
The conditions for a stalemate are precisely those described above. In particular, the following actions will not break a stalemate:
- Mine minerals or gas without returning them to a base
- Begin production of a unit, construction of a building, or research of an upgrade without finishing it
- Damaging but not destroying an enemy building
- Destroying a non-enemy building (e.g., a neutral Supply Depot)
- Damaging or killing any unit
- A game can result in a tie without having a stalemate, if players/teams lose their last building simultaneously. This can occur if the last buildings are hit with a Nuke.
In Wings of Liberty and Heart of the Swarm
Due to the change of timing in Legacy of the Void, the timings are different in the last expansion than in Wings of Liberty and Heart of the Swarm. In the previous expansions, the 129 seconds corresponded to 3 minutes (180 seconds).