Here is the full list of all 20 Untitled Ghost Game achievements.
Launched the game
Identify a ghost correctly for the first time
Identify a ghost correctly 10 times
Identify a ghost correctly 50 times
Identify a ghost correctly 100 times
Identify a ghost correctly on max difficulty
Buy 3 things from from the shop
Find the radio
Play multiplayer with 1 or more people
Obtain a total of 1000 Dubcoins
Use the Mirror in any difficulty
Surpass level 1 and become an official ghost hunter
Get to level 25
Get to level 100
Let one of your friends die in a match
Let one of your friends die in a match and also still guess the ghost right after, using their death as a step ladder to help you win (which is bad).
Play Untitled Ghost Game at 3am in the Morning
OMG IS THAT A DOG IMAGE HOLY CRAP NOW WAY
Get in the 2004 Toyota Tacoma
Get the silly little red guy easter egg