Mass Effect, Mass Effect 2 & Mass Effect 3
The elcor are a Citadel species native to the high-gravity world Dekuuna. They are massive creatures, standing on four muscular legs for increased stability. Elcor move slowly, an evolved response to an environment where a fall can be lethal. This has colored their psychology, making them deliberate and conservative.
Elcor speech is ponderous and monotone. Among themselves, scent, slight movements, and subvocalized infrasound convey shades of meaning that make a human smile seem as subtle as a fireworks display. Since their subtlety can lead to misunderstandings with other species, the elcor often go out of their way to clarify when they are being sarcastic, amused, or angry.
Dekuuna's high gravity impedes mountain formation. Most of the world consists of flat, open plains, which prehistoric elcor wandered across in small family bands. Modern elcor still prefer open sky, and can become restless and uncomfortable on long starship journeys.