The Onryo is the only ghost able to attack regardless of Sanity if you are particularly unlucky.
How to Determine a Ghost Is an Onyro
The Onryo can give the following three evidences:
Spirit Box Ghost Orb Freezing Temperatures
None of them have anything to do with its special ability, which is that the Onryo can attack whenever a Candle has gone out regardless of Sanity. This means that, if you are particularly unlucky, this ghost can initiate a hunt as soon as a Candle goes out near it even at the start of a round.
How to Survive an Onryo
An Onryo hunt can happen whether a Candle is tossed and manually extinguished by a player, by its flame simply running out, or by the ghost blowing the Candle out itself. Which it absolutely will do — Onryo will blow out Candles just like any other ghost.
The risk of this happening is compounded as players die in multiplayer. For each player death, the chance rises for the Onryo to initiate a hunt when a Candle is extinguished. When two players have been killed, the ghost is almost guaranteed to initiate a hunt when a Candle has been extinguished.
Like the Raiju, which serves as a counter to general play, the Onryo is a counter to clean play in Nightmare mode and can spell trouble for players on on lower difficulties who manage their Sanity using Candles.
Using Candles for Sanity management is mandatory in Nightmare, making the Onryo deadly when playing on the difficulty. You carry one around, you place them around the map, Candles are normally your only real friend in Nightmare mode. When dealing with an Onryo, they are your worst enemy.
No matter the difficulty, if you still have objectives to obtain after determining the ghost is an Onryo, it’s best to leave your Candles unlit once they go out.
On the flip side, this ghost’s disdain for putting out flames can make it easier to discern than some other ghosts. Though that is little comfort on Nightmare, as the extra stress of repeated hunts during low Sanity can make dealing with an Onryo a no-win situation.
Hopefully this guide has helped you better understand the threat of the Onryo. Check out our guides on how to survive The Twins and how to survive a Raiju in Phasmophobia.