Here is the full list of all 27 Super Sanctum TD achievements.
Kill 10.000 Walkers.
Beat all levels on Hard.
Get all stars in all levels on Hard difficulty.
Beat a wave with only skills and blocks.
Have no blocks at the end of a level.
Kill 10 enemies in a single Penentrator shot.
Kill a Walker with an Anti Air Tower.
Kill the golden Walker.
Beat all levels on Normal.
Clear Elysion
Clear Brightholme Industries.
Kill the Patriarch.
Kill a Huge Walker.
Kill the Charger and all its clones.
Unlock all towers and skills.
Clear the Hydro Islands.
Kill a Big Walker.
Unlock all tower and skill slots.
Clear the Facility Compound
Get 100 perfect rounds.
Hit 10 enemies with Thunderbolt.
Complete a level without using any skills.
Beat a level on Hard.
Kill 10 enemies with a single shot
Clear the Training Area.
Kill 2 enemies with a single Bomb.
Complete one level.