a "battle" could be defined when more then some percent of your army is engaged, for more then few seconds. maybe more then 15% for more then 15 seconds. I like the idea of battle music slowly fade after battle then few seconds of just quite (Add a very quite sound effect of whisteling wind). By the way, I really appreciate Omri's work. I think there should be another music: "getting ready for battle" witch is an energetic mix between relaxing "peace" and epic "battle". I remember warcraft II had these types of music and this really got me into the mood. For the condition in witch to play: Maybe when one of your troops is being attacked by an enemy force, or even when in peace time, but you have really big force of soliders, elefents, ballista or whatever just waiting for your command.