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.
Deal at least 500 damage in a single strike in Secrets of Legendaria.
Free Vallamir.
Crashed Combat Arena X.
Crashed Walk
Receive 4 card readings from Catarina in Walk.
Wooed a Great Kraken.
Perform a 360 No Scope with the sniper rifle.
Crashed Waste World.
Discovered the truth about Mr. Shrewd.
Buy 10 upgrades from the Scrap Shop in Waste World.
Crack all the vending machines at The Six Pint.
Crashed Secrets of Legendaria.
Find Missing No. in Secrets of Legendaria.
Crack a soda vending machine at The Six Pint.
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 Super Weasel Kid '09.
Learn all of Catarina's secrets in Super Weasel Kid.
Opened The Hex.
Completed ???'s memory.
Help Rebecha survive the first wave in Walk.
Completed Lazarus' memory.
Completed Rust's memory.
Activate a gated mod in Waste World.
Completed Chandrelle's memory.
Completed Bryce's memory.
Completed Super Weasel Kid's memory.