Heat is one of the strategic considerations in every engagement. If a 'Mech's heat exceeds the overheat threshold at the end of a turn, it will take internal structure damage. The threshold is 50% + 5% per point of Guts of the 'Mech's heat capacity. Reaching the end of the heat capacity will cause a shutdown and require a turn to reactivate the mech.
- Firing weapons. Generally energy weapons cause the most heat and ballistic weapons the least.
- Jumping causes 7.5 heat per jump jet
Heat is removed by heat sinks. Every 'Mech gets 10 heat sinks included as part of their reactor. Some 'Mechs may mount additional heat sinks. Standing in water doubles the effectiveness of heat sinks, and the biome also has a significant impact on heat sinking.