skill_cast_db.txt check it in db/pre-re if your using prere
check it in db/re if your using renewal
//===== Guild Skills =======================
//-- GD_EMERGENCYCALL
10013,0,0,0,0,300000,0,5000
// SkillID,CastingTime,AfterCastActDelay,AfterCastWalkDelay,Duration1,Duration2,Cool Down,Fixed Casting Time
change the cool down to your liking