Here is the full list of all 17 Tower of Guns achievements.
Kill That Dang Wall of Turrets Three Times
Pick up 1000 Health Items While at Full Health
Reach Endless Stage 14
Find and Level The Motivator Gun to Level 5
Tilt 10 Times in a Single Stage
Unlock all the Guns
Unlock all the Perks
Accumulate 888 Gold In a Single Run
Discover the Secret Code
Complete a Stage After Firing Exactly Fourteen Shots
Jump and Remain Airborn for 45 Seconds
Pick up Four Difficulty++ Badges in a Single Life
Die while a Boss is Exploding
Complete a Stage without Picking up ANYTHING
Kill over 350 Mobs in a Single Level
Stomp a Hugbot to Death
Complete a Stage Without Anything but the Boss dying