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