Well, its relativly easy.
You can also control braindead monkey humanoids from the clonebay , and i think that this should be nerfed. Maybe, a lively and juicy brain of RD for example, that can give sustance for the borer, and maybe add some sort of evolution menu akin to changelings, exept borer need to gain a certain amount of "brain power" before he can unlock his powers. It can be normal "chem borer"; or it can be a mutant strain that gives random power from vampire or changeling, after infecting host for some time; the last will be "mimic" - it can turn invisible when standing still and when stay long enough inside a host, can hide him too. As for objectives, besides "live and reproduce", it can be ordered to infect and keep a certain host until the end of the round, get borers to infect at least 1 host in each department, exept captain, or, at random, forcing a newcome borer to become a part of "infector strain", that spread the disiease, which makes people to move slow and do things longer, if they dont have a borer inside. But it can be spreaded only from infectors host with a touch and disease lasts for 5 minutes, it also massivly reduces sugar stun timer. The host himself become immune to any disease, while its borer cant breed. Another random strain can be "sindie borer" that molds the flesh of its host into a killing machine. As it infects a host, the effects begin to take appearance after 3 minutes. Then, you will take over your hosts body completly and you will have to find a safe place withint 1 minute timer. After that timer ends, you enter a cacoon, after short gestation period, now yours body turn into angry piece of very leathiry meat, as the mind of your host enters your rejuvinated borer body and goes on to repeat the cycle, you will have a sturdy and fast body with 2 armblades, that can breack airlocks. But, you arent exactly a golem, as well as its agains your interest to kill a potential host for your decendant. You dont have any means to paralyze and safely secure a host, instead, you'd have to guard your nesting place until cycle repeats few more times, before your mission begins - destroy all security and commanding staff on the station. But, not to drag this out for way to long, if no normal human remains on the station (and not anywhere else, like in CIT case) its a victory. However, you are strongly against butchering innocents, as sindicate imprinted a set of instructions upon your tiny mind:
1) Fufil your mission
2) Do not harm unarmed hosts
3) Attack only in defence - you must scare away your hunter, but do as less harm as possible.
4)Do not create envierment, hostile to the hosts.