The Gloam is a white specter that use the lightning spell. It can be found in Act 3 of Diablo II, in the Great Marsh. It can temporarily disappear from the screen when it is moving, but it is still vulnerable during this time. It does an incredibly high amount of lightning damage, even with 75% lightning resistance. It is highly recommended to wear gear like Thundergod's Vigor or Wisp Projector to help you stay alive. They are extremely dangerous, especially for Hardcore players. A monster pack with the Conviction aura is one of the hardest boss packs in the game. Dim Vision skill is a great help to prevent unexpected death from afar.