Risk of Rain Wiki

The Radar Scanner is an unlockable Equipment item in Risk of Rain 2.

Completing the Bookworm Challenge unlocks this item.

Activating this item creates a "?" over every interactable on the map, revealing their approximate location. These marks last for ten seconds and are present for all players. Since they are all the same size, determining how far away each interactable is sometimes difficult.

As this item reveals ALL interactables on the map, things like Legendary Chests, Rusted Lockboxes, and Newt Altars can be located with ease.

This item is the most reliable way of locating the Cloaked Chest.