Risk of Rain Returns Strange Battery: What’s It Used For? [Update]

[Update: November 11, 2023] We now have more info on what this Strange Battery does. Original story follows below.

[Original] The Risk of Rain Returns Strange Battery that can be picked up in the game at around Chapter 5 in confusing everyone. The item is located in an urn on the lefthand side of an elder temple. It’s not clear at first glance what the item is supposed to be used for, as the description for it only says “Bzzzt.” It looks to be some sort of necessary item that unlocks something, like putting it into an empty socket somewhere. Here’s what we know so far about the Strange Battery in Risk of Rain Returns for PC and Nintendo Switch.

How to use Risk of Rain Returns Strange Battery

[Update: November 11, 2013] The Strange Battery is used to unlock a character called Robomando, but the process is very complicated so get your boots strapped:

1. On Drizzle difficulty, find the Strange Battery in a pot near the Temple of the Elders.
2. Continue to the last stage and reach a hole behind some golems that appear beneath the map. Here you’ll find a chest where you can send items to a future run.
3. Turn on Rainstorm or Monsoon difficulty. Then head to the second stage and find a chest that has the Strange Battery in it.
4. Head to the third stage and defeat the Teleporter Boss, and interact with the teleporter at the 22-minute mark precisely.
5. On the fourth stage, a dead robot with a battery slot will appear. Place the Strange Battery inside and attempt to fight the robot. There’s no way to win this fight, but you will unlock Robomando as a result.

[Original] The purpose of the Strange Battery in Risk of Rain Returns remains a mystery at the time of writing.

There have been some answers on the official Steam forums for the game as well as the Risk of Raid Reddit and Discord. But nothing is concrete at the moment.

One user says that the battery is used to activate a robot survivor, but if you look at the list of unlockable survivors, none of them require a battery to activate. Another user says that this is a necessary component to find an artifact, but the answer is rather vague and wasn’t all that helpful to the original poster of the thread. We scoured the Discord as well but the supposed answers mainly led to dead ends.

The one thing that might be a clue is that in a datamine of the game, there seems to some kind of machine that uses the battery. This machine, though, is currently unidentified.

On Twitter, a user named Chin asked a general question about what the Strange Battery equipment is supposed to do. Developer Hopoo Games actually responded to the question but only with a pair of wide eyes. At the moment, there is not even a page on the Strange Battery in the official Risk of Rain Returns Wiki yet. Basically, no one has figured out what this item is supposed to do yet, but we’ll update this once something has been.

For more Risk of Rain Returns guides, here is a fix if Bandit did not unlock for you in multiplayer and more info on cross-play and cross-progression.