comparision for friendly bosses and instance / raid bosses
Lua Code:
local isFriendlyBoss = UnitIsFriend("player", unit) and UnitLevel(unit) == -1
local isInstanceBoss;
for i = 1, 5 do
local bossGUID = UnitGUID("boss"..i)
if UnitGUID(unit) == bossGUID then
isInstanceBoss = bossGUID
break
end
end