History of Chronolog

Chronologs are a currency added with the Ash & Iron update. They are spent at the Monument to Seasons Past to buy past Reward Pass items, including ones that were missed when they were first available. Real-money purchases are not possible.

In the Ash & Iron and Reclamation seasons, Chronologs were earned mainly on the Reward Pass. The free and Premium tracks each gave 1,500, and the last Chronolog drop was at Pass level 108. Items at the Monument cost between 100 and 300 Chronologs, depending on rarity and where the item sat on its Pass. Vanguard Alerts also give a 50 Chronolog bonus for completing the first stage of the Vanguard Alert.

The source describes the 2025 seasons and says future Passes may not be as generous, so costs and earning rates may have changed.