 Other alien races seen in the game include the reptilian krogan and drell, the environmental-suited quarians, and a hostile race of networked artificial intelligences called geth.During the events of the original "Mass Effect", a geth army attempted to open a portal for the Reapers, a highly advanced machine race of synthetic-organic starships that are believed to eradicate all organic civilization every 50,000 years.The galactic community has since lived in fear of another possible invasion.