Here is the full list of all 15 Siren Head: Awakening achievements.
Kill siren head using the gas station trap.
Set up siren head's trap at the gas station.
Commit suicide with the gun found in the secret bunker.
Complete the game in hard mode.
Find the sh***** graffiti.
Collect 5 flashlight batteries in hard mode in one game.
Escape with the repaired car.
Complete the game in normal mode.
Repair the broken-down car.
Collect all the car parts in one game.
Collect the 5th note found in the secret bunker.
Unlock the secret bunker.
Collect all the survivor notes in one game.
Complete the game in baby mode.
Collect all the car parts and survivor notes in one game.