Here is the full list of all 28 The Hex achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Crashed Walk
Receive 4 card readings from Catarina in Walk.
Free Vallamir.
Wooed a Great Kraken.
Perform a 360 No Scope with the sniper rifle.
Crashed Waste World.
Discovered the truth about Mr. Shrewd.
Crashed Secrets of Legendaria.
Score a 1000 hit combo in Combat Arena X.
Score a true KO on Alley Gator in Combat Arena X.
Complete the original Super Weasel Kid without any help from Mr. Shrewd.
Crashed Combat Arena X.
Learn all of Catarina's secrets in Super Weasel Kid.
Crashed Super Weasel Kid '09.
Crack all the vending machines at The Six Pint.
Opened The Hex.
Completed ???'s memory.
Help Rebecha survive the first wave in Walk.
Completed Lazarus' memory.
Completed Rust's memory.
Buy 10 upgrades from the Scrap Shop in Waste World.
Activate a gated mod in Waste World.
Completed Chandrelle's memory.
Find Missing No. in Secrets of Legendaria.
Deal at least 500 damage in a single strike in Secrets of Legendaria.
Completed Bryce's memory.
Crack a soda vending machine at The Six Pint.
Completed Super Weasel Kid's memory.