Here is the full list of all 38 Tentacular achievements.
Happy Birthday!
You've discovered an alien spaceship
You're cleared to work with M.A.G.N.E.T.S
You're Not From This World
The crystals are called Tentaculum in your honour
You and Mollusk have unearthed the crystal's biggest secret
You have defeated Mollusk's big bad robot
Beat the One Small Step side missions
Help a criminal entrepreneur
Build a new restaurant for Madame Gurnard
Renovate the mayor's villa
Beat the 2nd stacking challenge
Beat the 3rd stacking challenge
Beat the Merchandise side mission in under 2:30 minutes
Beat Bon Appétit side mission in under 7 minutes
Beat Doll House side mission in under 2:00 minutes
Build the statue in under 4 minutes
Build the high rise in under 3 minutes
Beat the 3rd stacking challenge in under 3 minutes
Assemble the satellite in under 1:45 minutes and all by yourself
Beat your boss in under 5:30 minutes
Throw the concrete block over 400 meters
Throw the concrete block over 200 meters
Take close-up photos of people in 22 different levels.
Get all 20 shipping containers out of the area in the Merchandise side mission
Use only 7 astronaut cages to solve the mission
Beat all main and side missions in the game
Don't miss any object being hurled at you by the cannon during your job evaluation
Save the workers after the factory accident using only 10 Zappers
Build the John Dory statue by only using the wobbly magnets. Don't use any supporting structure
Finish Blasting off with Mollusk with the least possible rockets used
Finish One Small Step with the least possible rockets used
Eat a piece of your birthday cake
Find and eat all the peanutbutter barrels in the game. Unlocks super large tentacle mode.
Pet all the dogs on La Kalma
It's a real crystal crisis! We have to save all the ships and get them safely into the harbour.
Free all the workers after the M.A.G.N.E.T.S. accident without using the powerline.
You've managed to assemble the satellite all by yourself