Here is the full list of all 53 Gamedec achievements.
The base game contains 52 achievements, and there is 1 DLC pack containing 1 achievements.
Make Ken a pretty straightforward proposal.
Gain Trolls respect in the bar.
Help the Bandit escape in Harvest Time.
Surprise Jester in the theater.
Complete all the fetchquests from Troll King.
Destroy the simulation
Escape from the simulation.
Agree with the simulation owners
Help Rhonda find her son.
Gather a team of at least 3 people.
Lock 3 characters in the loop in Paradise Beach.
Get to the Paradise Beach.
Visit 15 different locations in Axis Mundi.
Find the Panda's diorama in Axis Mundi.
Find Bliss in Axis Mundi.
Find Morty the robot in Axis Mundi.
Unlock all codebreaker modes.
Find the Harvest Time rift.
Break out of the prison.
Collect 3 memories of Ken.
Do 5 quests for the Clan Masters in Knight's Code.
Collect 10 iron.
Create 5 items in the Forge in Knight's Code.
Get to the Umbra's House.
Gather 3 Poteto Gomuins in Knight's Code.
Use the cat go through the gate.
Create Ken's V-Ghost from his psychoscan.
Use the brainfix on yourself.
Order a whiskey at Yet's bar.
Gain Sleeves respect in the bar.
Search all the trash bins in Fallen Hero.
Explore all death hypotheses in Fallen Hero.
Meet the diginet in the street.
Win a gun duel with the sheriff.
Use your deduction at least 15 times.
Get a gun in Harvest Time.
Listen to the 3 tales from the Rusty Ed.
Get 5000 Harvest Time's coins.
Find two ways to reach the graveyard.
Fully expand your farm in Harvest Time.
Get the maximum profession tier in at least two paths in one playthrough.
Get 50 information for deduction.
Reach the Farm Level 5 in Harvest Time.
Find all the clues written on the boards.
Help Fredo in Like Father Like Son.
Obtain the maximum profession tier.
Help Ramon to force another player out from Twisted & Perverted.
Get 20 aspects.
Get 50 pieces of information for the codex.
Help Starlett get out of limbo.
Complete the solitaire in Haggis' office.
Scratch Haggis' golden frame.