Faceless 3D model

The Faceless is an alien enemy encountered in XCOM 2. It serves as the aliens' primary infiltration unit, replacing the Viper's Thin Man form.

This unit disguises itself as a normal-looking civilian until provoked, whereupon it transforms into its true, alien form. Unnaturally tall and consisting of a gelatinous fluid, these alien foes have significant reach with their claws. The Faceless can move both farther and with more agility than may be expected from their size and lumbering gait.

The threat of this unit being hidden among the general populace in conjunction with civilians having a chance of removing concealment from the squad makes not only civilian rescue missions, but civilians in general much more of a liability.
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