Here is the full list of all 16 Mega Demon Blaster achievements.
Die
Unlock everything
Complete one run
Complete 50 runs
Kill 100 enemies
Kill 1000 enemies
Kill 10000 enemies
Complete a run with Vulcan
Complete a run with Rip & Tear
Complete a run with Metal Storm
Complete a run with Death from above
Complete a run with BFG 90
Complete a run with Bullet Nova
Complete a run with Lead Blades
Die 50 times