A scarab, also called Dwarf Gekko, are small machines like the Mk. II, but they are enemies outfitted with machine guns and infrared sights. They guard Shadow Moses in Act 4, together with Gekkos.
A scarab has three arms, which they walk on, a beam searchlight which they use to look for enemies, as well as the machine gun mentioned above. They attack either by using their machine gun or by hanging onto Snake, making him suffer damage. When there is a Caution or Alert, their numbers increase heavily, and they will be hard to get past without chaff grenades.
 How to Defeat or Sneak Past
Seeing as scarabs can only look in one direction, the way the blue line from their eye is directed, all you have to do is to stay out of their view. It is not smart to shoot them, as this will trigger a caution on the second. The best way to trick them is by either throwing out some chaff (alas, chaff grenades are rare in this game) or by distracting them with an empty magazine. By using chaff grenades, they will be unable to move, look, or shoot, in other words making them paralyzed. Using an empty magazine will make them investigate the place you threw the magazine, but they will go back to their post when the danger is declared.
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