I initially spoke with Winter about this particular idea on IRC, and he encouraged me to make a post and get feedback from the community about it, so I'll submit it here as both a request, and a topic for discussion.
The Vector Lance:
The Vector Lance can be accurately thought of as a giant, weaponized syringe. Essentially the weapon is a hollow, short lance about the size of the Kerrblade made from lightweight alien composites. At one end is an extremely sharp, monomolecular spearhead. At the other, a hinged lid. The spear is loaded with cylindrical tubes at the lidded end. These are compartmentalized into two sections; one filled with XVI and nutrient solution, and another with powerful tranquilisers. Two buttons are present on the device; a toggle to open and close the lid and eject or install the tubes, and another to extend and withdraw the spearhead by means of powerful integrated pneumatics, which cause the spearhead to thrust into a target with a great deal of force, rendering it capable of penetrating even heavier armours.
Shortly after activation of the pneumatic mechanism, the contents of the cylinder begin to rapidly discharge through the spearhead into its victim. The tranquilisers have the effect of inducing a short lived, near instantaneous unconsciousness, and also act as a facilitating temporary immunological suppressant while the XVI goes to work. After a period of time (several turns, approximately, the exact length may be determined by the health of the target), the XVI successfully subverts its victim, and it becomes a new member of the alien hive mind, awakening shortly after its infection is complete.
If PHALANX possesses a working anti-viral cure, it may prevent an infected victim from turning by administering it via the medikit, before the infection resolves. A fully turned victim however, cannot be saved, and must be pacified along with the remainder of the alien presence. If a battlescape scenario ends before a turning is complete, the victim is considered to be saved if PHALANX possesses a functional anti-virus. Otherwise, that victim is lost and is counted as a casualty.
The aliens will use this weapon on civilians as well as PHALANX soldiers. Civilians that are turned will attempt to assist the aliens however they can; commonly by serving as reconnaissence or engaging PHALANX soldiers in combat if armed.
Obviously, PHALANX cannot effectively utilize this weapon against alien forces. While the spearhead is easily capable of penetrating most types of armour to inflict injuries, these will prove non-terminal in nearly all cases, as it was designed to infect enemy forces, not to kill them. Given its size and relative lack of lethality, nearly all alternative melee weapons will make for superior choices in close quarters combat.
Bloodspiders may also be retrofitted to use similar devices. Given their speed, resilience, and increased fluidic capacity they would prove to make ideal transmission vectors, each being easily capable of administering many fast-acting doses within a relatively short period of time.
So, what does everyone think?
