Physically, SCP-513 is an unremarkable, rusty cowbell. No marks or engravings are visible on its surface due to the large amount of corrosion. Attempts to remove the rust chemically or mechanically have had no success.
Any noise produced by SCP-513 immediately induces strong anxiety in all sentient beings who hear it, regardless of their previous mental status. Exposure victims report feelings of being watched by an unseen entity and present elevated heart rates and blood pressure.
SCP-513 can be found in its containment chamber inside a protective gelatin, which is halfway melted. If the player picks up SCP-513, it can be rung by double clicking it in the inventory. After this, the player will begin seeing SCP-513-1. Sometimes, after ringing SCP-513, the players vision will automatically turn toward any monitor, and experience hallucinations, just like when viewing the monitor in SCP-895's containment chamber.
Roughly one hour after exposure to SCP-513, victims will begin to catch glimpses of SCP-513-1 when opening doors, walking past mirrors, turning their heads, or performing any other actions that result in a sudden change in visual perception. Upon being sighted, SCP-513-1 reportedly turns away and runs out of view before disappearing without a trace. Questioning of bystanders indicates that SCP-513-1 is invisible those who have not been exposed to SCP-513.
Sightings of SCP-513-1 reoccur every 14 to 237 minutes. This "stalking" behavior inevitably causes extreme sleep deprivation, as victims are frequently disturbed by SCP-513-1’s presence in their quarters. Victims able to fall asleep before SCP-513-1's appearance report being physically assaulted by it. Upon the victim's awakening, SCP-513-1 flees as usual. This sleep deprivation, along with the mental stress caused by SCP-513-1's behavior, invariably induces paranoia, aggression, hypervigilance, and depression. All test cases but one have ended with the test subject’s suicide.
Descriptions of SCP-513-1's appearance are largely unreliable. Test subjects are unable to provide complete accounts of sightings due to their exhaustion, degraded mental health, and disruptive hypervigilance. However, all interrogations thus far indicate that SCP-513-1 is a tall, emaciated humanoid with abnormally large hands.
After the player rings SCP-513, SCP-513-1 will start stalking the player. The sound of loud breathing can be heard and SCP-513-1 will occasionally be seen in the player's peripheral vision. Attempting to get closer to SCP-513-1 will result in it vanishing or flying away (causing smoke). The only way to get rid of SCP-513-1 is to destroy SCP-513 by processing it through SCP-914. Upon destruction, the loud breathing will cease.
Currently, SCP-513-1 does not harm the player in-game, but can leave players on their toes.
- SCP-513 was re-added in build v1.0.8
- SCP-513 existed in older builds, but was removed because ringing it would always result in the player dying. It was replaced with SCP-372, in v1.0.
- SCP-513-1 model is an edited version of SCP-096.
- If SCP-513 is placed in SCP-914 on fine, very fine or 1:1, the game will crash.
- SCP-513, and SCP-513-1 itself is harmless.
- SCP-513-1 is the only harmless humanoid object in the game.