Smoker

Smokers are synthetic-organic creatures derived from quarians and volus and mutated by Reaper technology. They were first documented during the final confrontation with the Reapers on Earth, and may have represented an attempt by the Reapers to adapt to increased resistance by organics.

Description
The smoker is a hideous amalgamation of a quarian and a volus. The body resembles that of a suited quarian, but horribly elongated and riddled with Reaper machinery. A hollowed-out volus (or perhaps just the empty suit thereof) is attached to the creature's back and filled with gas, which travels via a tube from the volus' suit's facial port around to a port in the quarian's abdomen. As the creature shambles forward, it perpetually spews forth a toxic gas from the former quarian's facial port, threatening to poison any organic who approaches.

Some survivors of smoker attacks have reported hearing frantic, gurgled pleas coming from the creature as it drew close to them.

Capabilities
The smoker is capable of running in short bursts, but usually just stumbles forward. It is easily outrun in wide open spaces, but can be extremely dangerous in tight spaces. During the battle in London, Alliance troops reported seeing smokers in the city's tight alleyways, suggesting that the Reapers deployed them there for greater strategic effectiveness.