Warns you if you are standing too close to Sir Zeliek and might get hit by his Holy Wrath ability. Mostly useful for Warlocks I guess since the Holy Wrath range is just 1 yard shorter than Shadow Bolt's range.
>> I wouldn't recommend using this as the only method of positioning yourself. I can't guarantee that this is 100% accurate down to the yard so only use this as backup if the boss moves closer to you without you noticing for example <<