Flying mini-versions of the Nihilanth. When alerted of the players precense, they scream very loudly, also alerting nearby Vortigaunts and Alien Grunts. In Half-Life these appear to be used as slave drivers, overlooking Vortigaunts where they work. Can usually be downed by a shotgun blast or two.
Their attacks are similar to those of the Nihilanth, although the energy balls these shoot are much weaker and only harm the player much when the Controller is in a group of several other enemies.
Interesting to note is the similar look to the Nihilanth and the way the head opens when attacking.
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Alien Controller
