I have an interest in the SCP universe so decided to share my favorite one in hopes that you guys would be interested too. SCP-2935 is probably the most terrifying one I’ve read up on (even more so then 001 “When day breaks” or the Scarlet King) because of its entire concept. In case the video was too long (I implore you to watch the whole thing, it’s well worth it) here’s a brief description of 2935 SCP-2935 is essentially an inter dimensional entity that wipes out anything even remotely resembling life in the dimension it invades. This includes AI and anything with living cells within it. In the story of this SCP, a distress signal from a parallel dimension of one of the SCP containment sites is received by the equivalent dimension SCP site. The broadcast is a signal warning civilians to stay in their homes as their containment has been breached. It says it will broadcast this message from the date it says and right when it’s about to say when the broadcast will end, it loops to the start of the broadcast again. A Mobile Task Force (essentially SCP containment police) is dispatched to the cave where the signal originates from. Once they are through the cave they exit to an identical reality except it is completely silent with nothing but the wind passing by as everything in this reality died instantly with a complete cellular wipeout when 2935 entered it several days prior. The team stumbles upon corpses of adults and children who look like they have died very recently and the food they were eating looks fresh. All bacteria has died in this reality meaning decay is not possible. Once the MTF reaches this realities equivalent of the containment site in their own reality, they discover that everyone is dead and that the facility is in lockdown mode. Once it is lifted they discover that an indestructible SCP (682) is dead in its containment cell. The agents discover their counter parts dead on the ground with no decay except for one anomaly. One of the agents, Keller was not present at the site at the given time the event happened yet he discovers his corpse at the site that has decayed badly. A drone is sent in from the original reality to the dead reality and only agent Keller appears when the drone does reconnaissance. He sends the drone back to the cave to go back to the original reality and instructs the SCP foundation to seal the cave off and “lock it in here with us” and as the drone exits, it notices a nuclear explosion at the site the MTF was investigating. Keller 1 detonated this nuke because he realized something, the Keller who was decaying in this reality (Keller 2) was from this reality and was part of the same MTF that went to another dead reality to investigate a distress signal. When he returned to his own reality, everything around him instantly died. He returned to his own facility to see if there were any survivors and to no surprise, there wasn’t. He then recorded an audio log explaining what happened and that whatever this entity was, it had followed him to his own reality and instantly wiped everything out. Keller 2 was not killed because he was the one who brought it back. He then ends his log saying “I am become death, the funny thing is if you read this log, you are death too.” And proceeds to kill himself, this is why he is decaying. Keller 1 realized he cannot return to his own reality because it will kill everyone so he locks himself and his team in the site and detonates the site warhead, ensuring this entity could never destroy any other realities through piggybacking on the team heading back through the cave. The SCP foundation then blocks up the cave with cement and leaves it alone. This is a vastly oversimplified version of the story but please do watch the video or read the article on the SCP wiki, it’s an incredibly well done story and like I said, my favorite one. I may post more of my favorite ones eventually as well as I love the SCP universe.