Here is the full list of all 40 UnMetal achievements.
Reach the ground floor in less than a minute when rushing to save the doctor.
Heal 20 guards.
Die while tampering with items from your inventory.
Finish the game.
Finish the game on hard difficulty.
Finish the game without using a potty.
Destroy General X's robo-tank without using electromagnetic grenades.
Destroy 5 drones by punching them.
Break all toilet doors.
Complete the catacombs without destroying any cell gates.
Complete "Jerico's Heart".
Defeat TAKUMA TAKAGASHI without letting him heal himself.
Reach level 10.
Obtain Robert's photographs.
Destroy 9 mechanical spiders.
Have 90 or more bullets at the same time.
Complete "A Thousand Eyes Are Watching You".
Find 15 secrets in the game.
Complete "Boom Docks".
Neutralize 5 guards using the slingshot.
Obtain 5 potties.
Put 20 guards to sleep.
Reach level 8.
Get the maximum experience possible in at least 5 chapters.
Complete "Engineering Problems".
Defeat HUGEEL firing just 6 torpedoes.
Destroy 5 crates with the explosion of a single grenade.
Complete "The Barracks".
Destroy 5 trucks in the barracks north parking lot before SPLASH MIKE does with his tank.
Let SPLASH MIKE destroy all crates and trucks at the barracks.
Reach level 6.
Complete "Welcome to the Jungle".
Complete "In the Lion's Den".
Reach level 4.
Complete "Something Stinks Really Bad".
Defeat Sewerjunk without damaging it with the Flamethrower.
Craft a Molotov cocktail.
Kill 5 Human-Piranha-hybrid things with the shredders.
Complete "The Great Escape".
Reach level 2.