Here is the full list of all 19 RedEx achievements.
Buy your first weapon at the menu store
Buy your first supply in the terminal
Defeat Pickup Boss for the first time
Defeat Helicopter Boss for the first time
Kill Cyborg Boss in the Labs for the first time
Defeat every Boss in game
Buy Berrett M82 at the menu store
Your turret is destroyed by enemies. I'm sorry
Buy 3 turrets at the same time
Scratch up 100 Silver coins throughout one battle
Buy every weapon at the menu store
Fully upgrade your skills
You've got every achievement! Thanks for playing!
Destroy your Tesla Tower
Use toolbox for the first time
Buy your first spy computer
Place signal receiver for the first time
Unlock Veteran
Unlock Hidden