Per 
Special Containment Procedures: SCP-5531 is to be contained in a 3m x 3m x 3m containment cell. Surveillance equipment is to be placed within the containment cell and monitored at all times. Biweekly checks for any openings in the cell are mandatory. Four 3,500-lumen floodlights are to be installed in each corner of the cell. A rotation of staff with Level 4 or higher clearance are to clean the cell on the first day of every month.
Description: SCP-5531 is an insect-like creature that measures to be approximately 55 cm in length. The subject has a tail, with a stinger located at the abdomen. The subject's stinger is slightly less than 5 cm in length and consists of the same material as the shell protecting SCP-5531. It has small barbs to more easily enter the victim's body and is coated in ██████. The tail is approximately 1/3 of the subject's length. Six 25 cm appendages are attached to the body, which is protected by a seemingly indestructible shell. SCP-5531 is gray in color, and its skin is devoid of any hair. SCP-5531 sheds a thin layer of skin approximately once a month to retain hydration in the skin. Whether SCP-5531 has sight is unknown, but Dr. ███ claims that the subject does not appear to have any sense of vision. It has been documented that SCP-5531 is capable of jumping 5 meters from its original location, and can reach speeds of 30 km/h on foot. SCP-5531 will attack by jumping onto the front of its victim's torso. It will then proceed to tear through the victim's flesh while injecting what appears to be eggs into the stomach of the victim. SCP-5531's mandibles contain two rows of three cm long teeth that are able to tear through Kevlar with ease, as seen in Incident-5531-A. During this incident, the victim's body began to bloat until they would burst approximately three minutes after, turning the remains of the body into a slush material. It is unknown what exactly the egg-like objects are, as the victim destroys them in the process of bursting, although Dr. ███ states they may be ████. SCP-5531 shows extreme aggression to any organism within a radius of approximately 10 meters. It has been noted that SCP-5531 becomes extremely docile when exposed to bright light, upwards of 3,300 lumens.
Further testing is to be done as per orders of Dr. ███ to discover unknown details about SCP-5531.
Discovery: SCP-5531 was discovered after a concerning amount of people, mostly miners, were reported to have gone missing near cave-like terrain in ██████, ███. MTF Zeta-9 "Mole Rats" was dispatched and given orders to investigate the area. Shortly after going into the cave opening, MTF Zeta-9 Commander █████ heard 60% of his men get eliminated, claiming "the creature was unstoppable." The survivors were able to lure SCP-5531 into a containment cell which was transported by helicopter back to Site-███.
Addendum-5531-A: Experiment Log for SCP-5531
Experiment Log 5531-A
Date: ██/██/20██
Procedure: Each floodlight is hooked up to a dial that controls brightness in lumens. They are to be turned up 100 lumens per trial, starting at 3,000 lumens. The effects on the subject are to be recorded after each trial.
Trial 001 Results (3,000 lumens): SCP-5531 showed slight irritation, and slower movement. Recorded speeds peaked at 15 km/h. The subject appeared unable to lift itself off of surfaces.
Trial 002 Results (3,100 lumens): SCP-5531 showed similar effects to the previous trial. The subject was still able to move but did so less often. Recorded speeds peaked at 9 km/h.
Trial 003 Results (3,200 lumens): SCP-5531 struggled to cover any sort of distance. The subject moved no more than 3 km/h but did not seem to be physically harmed.
Trial 004 Results (3,300 lumens): SCP-5531 was unable to transport itself. The subject was capable of moving its appendages.
Trial 005 Results (3,400 lumens): SCP-5531 did not show any sort of movement and stayed in the northwestern corner of its containment cell.
Incident-5531-A: SCP-5531 appeared to be resting when it suddenly attacked two of the floodlights in quick succession, rendering them useless. Echo-1-3 and Echo-1-4 went to secure the containment chamber with the help of the stationed guards Delta-1-1 and Delta-1-2. India-2-1 was later called in for backup.
Aftermath Report of Incident-5531-A: During the time it took Echo-1-3 and Echo-1-4 to arrive to the location, SCP-5531 attacked the other two floodlights, disabling them. SCP-5531 was successfully locked to the eastern side of the cell for the floodlights to be reinstalled, and the janitorial team to clean up the remains of Echo-1-3, Delta-1-1, and Delta-1-2.
Addendum-5531-B: Experiment Log for SCP-5531
Experiment Log 5531-B
Date: ██/██/20██
Shell Durability Testing for SCP-5531
After Incident-5531-A, the durability of SCP-5531's shell caught the attention of O5-█, leading to the following tests: D-████ was ordered to fire a variety of firearms at the shell of SCP-5531 to test the durability.
Weapon: M1911 Pistol
Results: Three .45 ACP rounds were fired at the shell of SCP-5531. The rounds were crushed in the process. No visible damage was done to the subject, and SCP-5531 didn't seem to take notice to the attack.
Weapon: Desert Eagle Pistol
Results: A single .50 Action Express round was fired at the shell of SCP-5531. The ammunition was only crushed at the tip, making it blunt. No visible damage was done to the subject, and SCP—5531 didn't seem to take notice to the attack.
Weapon: MP7
Results: Ten 4.6×30mm rounds were fired, only eight hitting the target. All rounds were crushed in the process. No visible damage was done to the subject. SCP-5531 took notice to the attack, but was unable to attack D-████ as all four floodlights were on.
Weapon: ArmaLite AR-50
Results: A single .50 BMG round was fired at the shell of SCP-5531. The effect on the ammunition was similar to that of the .50 Action Express round. No visible damage was done to the subject, however SCP-5531 was shifted 3 cm back when contact was made.
Weapon: RPG [REQUEST DENIED]
Note from Lead Researcher █████: SCP-5531, as of ██/██/20██, is beginning to build a resistance to the floodlights installed in its containment cell. A request for termination trials may be made if the floodlights are required to exceed the current 3,500 lumens. It is a requirement that the subject's containment cell is made more durable in the case of this event.
