You use something along the lines of:
Events.EndCombatSim.Add( MyOnCombatEnd );
Whenever a Combat ends, a function you've previously defined as follows:
MyOnCombatEnd( m_AttackerPlayer, m_AttackerUnitID, m_AttackerUnitDamage, m_AttackerFinalUnitDamage, m_AttackerMaxHitPoints, m_DefenderPlayer...