SCP-1662-A through -D are to be kept in separate 3m x 3m x 2.5m cells of 8.8cm thick transparent armor lined in one-way laminate to prevent the instances from observing one another while still allowing the constant monitoring from the outside.
This is a long sentence that can be shortened by removing "to prevent the instances from observing one another while still allowing the constant monitoring from the outside", because the quoted part is generally self-evident if you're using one-way laminate.
Instances display signs of sapience, and possess the ability to write in and understand various languages, which vary based mostly on the region the instance inhabits, as well as the knowledge of an at this time untranslated written code consisting of dots, various shapes, and the numbers zero (0) through seven (7), used presumably for communication between instances.
Really, really long sentences.
SCP-1662 will then follow the imprinted individual and deliver SCP-1662-1 personally, until the point that delivery is made, or the individual no longer fulfills the requirements
Deliver until the point that delivery is made? It seems a little redundant? Or maybe you should remove the last comma there, so it goes 'deliver it personally, until the point that delivery is made or the individual no longer fulfills the requirements' or something? This sentence was confusing to read.
or so the legend goes
I question how a person speaks in underlines as opposed to bold? Small and unsignificant point though.
Overall, I like it, but I don't understand that it is stated that they are unable to speak, but the -D guy speaks very well? Or am I doing something wrong? It feels a bit lengthened and overly complicated for what it is. +1 regardless, but I think it can do with some fat trimming.