Here is the full list of all 67 Turbo Overkill achievements.
Finish every level on Serve Me Pain or higher
Finish every level on Murder Machine
Finish every level on Regular Joe or higher
Finish every level on Street Cleaner or higher
Finish every level on Virgin Blood or higher
Complete Final Purge
Complete Episode 3
Finish Turbo Overkill
Complete Teratek Showdown
Defeat The Monstrosity
Complete Vector-4
Have over 100,000 Zhen in your current account
Complete Terminal Eclipse
Kill up to 25 enemies while in Turbo-Time
Complete Sunset Synthetica
Stay off the ground for 30 seconds or more
Fire a rocket, grab it with the plasma gun, and kill 5 or more enemies with it
Destroy the haunted machine on Sunset Synthetica
Get all weapons and upgrades on a single save slot
Complete Night Ride
Complete Infestation
Kill a Rammer with their own Mace
Complete Scrapyard
Complete Refactor
Complete Episode 2
Complete Napalm Blitz
Defeat the Bounty Hunters
Complete Pressure Point
Defeat Ripper in under 5 minutes without dying or reloading
Complete The Wastes
Complete Exodus
Complete Outskirts
Get eaten by Jimmy the worm in Outskirts
Complete Teratek Factory
Complete Toxin Refinery
Complete Paradise Lost
Complete Artifact-Zero
Complete Episode 1
Kill Artifact-Zero in less than a minute
Complete Rooftops
Complete Ascension
Complete Dead Plaza
Kill 10 or more enemies with 1 Launcher rocket
Kill up to 8 enemies with 1 Waster explosive shot
Complete Open Season
Complete Battle Alley
Kill all Dopefish in Open Season
Complete Emergence
Complete Syn
Find all Tech-Chips and Cassette Tapes
Get 100% kills on every level
Acquire all augments on a single save slot
Get beyond wave 20 on Endless on default settings
Get beyond wave 40 on Endless on default settings
Kill 15 or more enemies with 1 Ion Blaster beam
Kill Jazz with toxic slime
Finish Exodus without firing your hoverbikes minigun
Get taunted by Maw at the secret splice terminal in Terminal Eclipse
Finish Infestation without taking a hit while driving the car
Finish The Wastes on Serve Me Pain or higher without dying or reloading
Defeat Maw on Napalm Blitz without taking a single hit or reloading
Get denied entry to the No Chainsaws club in Battle Alley
Get eaten by a shark in Emergence
Kill Maw and his minions in the final arena of Night Ride with chainsaws only
Complete Vector-4 in under 12 minutes
Destroy the arcade cabinet in Scrapyard
Kill all enemies in the skate arena in Syn by only using your Chainsaw leg