Chasm -

The main questline to unlock the map and explore.

Found during the entry quest, requiring the destruction of Bedrock Formations. The main questline to unlock the map and explore

Defeating them grants items necessary for unlocking a secret room in the Upside Down City. The main questline to unlock the map and explore

Involves using Geo constructs on pressure plates to align and break large pillars. The main questline to unlock the map and explore

(like "Heavenly Stone's Debris")? The location of a specific puzzle (like the bedrock keys)? Lore details regarding the Abyss or the Nail?