Here is the full list of all 35 Time Rifters achievements.
Destroy 50,000 enemies with the Flak Cannon
Destroy 50,000 enemies with rockets
Destroy 50,000 enemies with the Plasma Beam
Get 100% on Episode 3
Get 100% on Episode 2
Escape every arena in Episode 3
Escape every arena in Episode 2
Destroy 50,000 enemies with the Scatter Pistol
Destroy 50,00 enemies with the Spread Rifle
Complete 10 Daily Challenges
Destroy 5,000 enemies with the Particle Ball
Complete a Let's Replay on any Episode
Destroy 5,000 enemies with the Flak Cannon
Destroy 5,000 enemies with rockets
Create & Upload a Custom Arena
Create & Upload a Challenge Room
Play a Custom Arena
Destroy 5,000 enemies with the Plasma Beam
Destroy 5,000 enemies with the Scatter Pistol
Complete 1 Daily Challenge
Escape every arena in Episode 1
Destroy 500 enemies with the Scatter Pistol
Destroy 5,000 enemies with the Spread Rifle
Unlocked Experiment mode for Episode 3
Destroy 500 enemies with the Flak Cannon
Unlocked Experiment mode for Episode 2
Destroy 500 enemies with rockets
Get 100% on Episode 1
Destroy 500 enemies with the Plasma Beam
Record a Let's Replay on any Episode
Unlocked Experiment mode for Episode 1
Destroy 500 enemies with the Particle Ball
Destroy 500 enemies with the Spread Rifle
Destroy 50,000 enemies with the Particle Ball
Complete 50 Daily Challenges