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The Combine Assassin is mostly a slimmer and female version of the Overwatch Elite, with an almost identical helmet. She uses two automatic pistols (and originally some kind of rifle), and a variety of melee attacks. She is shown to be a quick and resourceful enemy, moving swiftly and performing flips, rolls, and other movements. She also wears heel springs, recycled as the Advanced Knee Replacement for Chell in Portal, that improves her movements and speed. The armor and padding are almost completely absent, allowing the assassin to move quickly. When she dies, the light on her helmet slowly goes off.