E-Sauro is a Dinosaur brought back to life through a reanimation program. The flesh of a recently diseased body is tough, so reptiles were mostly used for durability.
These robots are programed with specific duties:
E-Exterminator
H-Hunter
D-Defender
S-Scout

Sauro is an Exterminator programed to take down a resistance leader. However, she was actually revived through the reanimation project, making her the only unit to think independently. She is highly skilled.