Vaal Vessel

A Vaal Vessel is a loot container found near the boss in all vaal side areas. It can only be opened after the boss has been defeated. It always contains Vaal Skill Gems or Vaal Fragments. Sometimes it contains corrupted gear.

A unique version, Atziri's Vessel, can be found in the map. Opening it will complete the map objective and it will drop multiple Sacrifice Fragments or Vaal Skill Gems.

Drops
According to Chris, the base spawn rate of loot is as follow:
 * a Vaal Skill Gem (50% chance) or
 * (20% chance) or
 * (15% chance) or
 * (10% chance) or
 * (5% chance)

However, this does not take into account on the introduction of card in Version 3.7.0 as well as vaal side area rework in Version 3.10.0, so that the spawn rate may be outdated.

Depends on the modifiers of the vaal side area (in spawn weight table known as "secret_area"), there are additional loots from the vessel. It has a chance to drop the divination card (does not require the mod mentioned below) as well as other cards that give corrupted items if the area has  mod.

Version history

 * Added many new mods that can appear on Vaal side areas, including several that can influence the items and rewards found in those areas.


 * Vaal vessels found in Vaal side areas or by placing a Vaal fragment in the map device now drop more items.


 * Introduced to the game.
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