Vanish is a status that causes duplicate dice to immediately disappear. For example, a roll of 1, 6, and 1 will change to a roll of 1, 6. This prevents the use of equipment that activates with doubles. If a dice-modifying piece of equipment rolls matching dice, the created dice that match will be destroyed.
During the Compression Errors Robot episode, the Robot is permanently inflicted with Vanish.
Permanent Vanish on both player and enemy can be added as a Bonus Round rule with the Wisp rule.
In the Reunion DLC, there's also the Fade status, which is a version of Vanish that disappears when triggered. It is only caused by Sheer Will.
This effect is only caused by two pieces of equipment in the base game: