Leper

Lepers are hostile aliens in Extinction.

The Leper often likes to stick to the outskirts of the map. If you receive the Challenge to "Find and kill the Leper in 30 seconds", it is helpful to use Feral Instincts to find it. The Leper's face will glow bright red to a player with Feral Instincts activated.

The Leper appears to be the only alien that intentionally runs away. Often this is the only distinguishing characteristic.

The Leper can be seen running from a rhino in the farm section of extinction.

Trivia

 * Lepers have very similar appearances to Hunters. Lepers do not glow, however.