Season 26 of Diablo III will bring with it a brand new activity in the form of the Echoing Nightmare. The new activity, as well as updates to the game’s Greater Rifts and item set changes, will be available for testing on the game’s public test realm starting March 10.

As detailed in an official preview blog, the Echoing Nightmare is a seasonal-character only activity where players will battle against the increasingly dangerous memories of fallen Nephalem warriors. Players will need to acquire a Petrified Scream from defeating a Greater Rift Guardian and then transmute it in Kanai’s Cube to gain access to the nightmare. Rewards for the new activity include legendary items, blood shards, gems, and a new legendary gem, Whisper of Atonement, which is used exclusively for augmenting Ancient Legendary items.