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