Notes:

By Zhange000 on DeviantArt.

This higher res image was found on this Reddit thread in the r/SCP subreddit.
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In the climactic end of the search & rescue mission of Mobile Task Force Tau-5 “Samsara” to save the lost mobile units and still remaining foundation personnel trapped in Site-13, the task force and the group of survivors are being pursued by a black tentacle monster. In order to buy more time for their escape, a few members of Samsara open the containment cells of two powerful "Olympia-class" SCPs. Though not explicitly mentioned by name, it is heavily implied that the two other SCPs are SCP-001 "The Gate Guardian" (Dr. Clef's Proposal) and SCP-2845 "The Deer." The group of humans, dwarfed by the size of these three creatures, are caught in the middle of their epic fight as they try to make it back to the surface and finally escape.

SCP-1730 – "What Happened to Site-13?"
SCP-001 – "The Gate Guardian"
SCP-2845 – "The Deer"