Per 
Castle of Reflection
Euclid? SCP in the form of an old, unfrequented castle where in the puddles of liquids (most often from rain, but other liquids have been tested to various degrees of intentional and success) people's footsteps can be seen, but not reflections of those people (for water reflections at least). stepping in the puddles seems to prompt reactions from the other footsteps in the puddles, with the aid of mirrors it generally seems to be of surprise from the shadows. activity viewed from these footsteps (frequency, formation) seems to indicate they mimic the activity of old peasants and knights that may have once lived in the castle. any and all mirrors (or intentionally reflective surfaces) brought within the castle immediately fog up and only indistinct shadows can be seen moving about (sometimes sitting atop four legged shadows, assumed to be horses), and all of these correspond with footsteps in water puddles. Only one mirror seems to function "normally" within this SCP, sits at the top of one of the main towers, but the "reflection" does not display the viewers or the room normally, instead showing a usually empty (See addendum) room filled with filled with furniture and bedding typical of a 13th century medieval castle. A workbench can be partially seen beside the mirror, what can be seen on top of it seems to be ingredients and books typical of a warlock, wizard, alchemist, etc.
incident report could be from typical maintenance when someone fell or cut their self and bled enough to make a puddle, redacted interactions perhaps? Probably lets people get a clear sight of the "inhabitants", and the inhabitants get a clear view of the people.
Redacted interaction, see splashes in water as if something is dragged away, person disappears…
Banshee? (Euclid)
Probably made already in some way, ghostly entity subsists upon emotions (ability to subsist on emotions beyond the "negative" emotions found out later in containment, though sadness or joy seem the most satiating). Actively seeks out any entity capable of emotions and drains them to a point of depression or a daze, sometimes death depending on shock or other factors.
Capable of moving through most barriers similarly to a ghost when hunger builds up enough.
visage of a young women, ears slightly pointed, eyes deeply set and blackened, appears more solid after having recently eaten. Hair is unkempt, signs of abuse visible when solid enough.
Gacha Post (Safe)
A sign post for a 30 mph speed limit that when an animal is tied to it by a leash, rope, or similarly functioning tool can switch it with another animal once sight is broken with the tied up pet. Observations of the rope during the "switch" indicate that it cycles through several different animals every second, given by changes in the leash's position and make up. The new animal, once observed, has an appropriate leash with adequate strength to restrain it (See Addendum).
Containment procedures would be a typical storage room in any of the facilities, given that it's size would prevent storage in one of the typical lockers used for "safe" anomalous objects. No special procedures necessary for containment, other than the usual inventory count to make sure it's still there.
Seems to be a normal speed post that could be found near the entrance to residential or urban areas anywhere in England. Specifically found near the shopping district of XXX, England. Dents and scratches consistent with a wide variety of animal claws along the metal post and the sign itself are the only immediate indication of anything anomalous. A sticker slapped onto the side advertises the semi-popular gacha game XXX-Luck, which involve collecting a variety of cutesy animals, investigation into the company pending.
Seems to function off of randomly picking from any population of animal, without accounting or size or number. Given this property, and various incidents from the experiments, testing is suspended until further notice. There could possibly be ranges of chances (common, uncommon, rare, etc.) assigned to different species, but testing was not done extensively enough to get a good enough gauge.
Possible switches include:
Lab rat tied by string to body with Asian elephant tied by rope to leg (Complaint about performing tests with animals inside Foundation buildings)
Asian elephant tied by rope to leg with deep sea angler fish tied by unidentified strand of fiber that almost immediately evaporated. (deep sea angler immediately ballooned before normalizing size, soon perished from lack of water)
Lab rat tied by string to body with human tied by spiked collar to neck (administered amnesiacs after interrogation on previous location, task force sent out to deliver amnesiacs to any people who witnessed the event)
Lab rat tied by string to body switched with ????? tied by unknown strand of fiber to one chitinous arm, identical to previous test with angler fish (previously unseen entity, similar to crustaceans with only 8 limbs instead, clicked in patterns to researchers before seemingly expiring, autopsy pending)
Lab rat tied by string to body switched with SCP-247 tied seemingly by normal pet leash. (Loss of 2 D-class and 1 researcher as the researcher did not immediately recognize SCP-247 and was promptly torn apart. SCP-247 did not seem to actually be tied to the post by anything, as the "illusion" of the pet leash broke as soon as it tore apart the first D-class. Previously unknown aspect of either the post or of SCP 247, assumed from interaction of two anomalous entities, testing suspended until further notice.
"We have hundreds of anomalous animals, each could be considered their own species, which, by simple logic, means there's a much higher chance of grabbing one of them instead of a "normal" animal, given what we know! This has been a safely contained SCP ever since we ripped it from the ground and put it in storage; suspend testing until further notice. Job done." - some doctor
"No, I don't care that your gacha collection is incomplete, Bright"
Geometric Kid (Euclid)
Kid who is obsessed with patterns and puzzles, can see them in otherwise random things, feels compelled to solve them, which reduces it to crystalline, perfect structures. Can "solve" people if not otherwise distracted or preoccupied by puzzles and games with strong patterns in them. If encouraged to be creative in how to solve a puzzle REDACTED, let the boy solve it his way, still dangerous but not THAT dangerous
