Synth Levels are determinents of how synthetic a being is. There are three Synth Levels
Pure bloods are unaltered organic beings.
Bionics are organic beings with synthetic components. They are what one could call "cyborgs". Their synthetic parts can be aetherium based or mundane, though all bionics have at least a few aetherium based components.
Automatons are either purely non-organic beings (what one might call robots) or near non-organic beings (ie someone who has their brain and, depending on the model, vital organs transplanted into an otherwise purely synthetic body). They are usually made up of aetherium and mundane technology, though the truly non-organic automatons can be purely mundane, while both purely non-organic and near non-organic automatons can be either a blend of mundane tech and aethertech, or comprised solely of aethertech.