Number of achievements: 30
Number of missable achievements: 1
Minimum Playthroughs: 1
Free-Roam After Story: No
Does difficulty affect achievements?: No
Time to 100%: 5-7h

There's only one truly missable achievement: Hint Hater which requires completing the game without hints. It's very easy to accidentally click the hint icon, I had to restart my game twice because of it, so be careful.
All other achievements, if missed, can be gained by mission select and shouldn't take more than a few minutes.
Achievements are split into chapters and presented in the order of acquiring. A few achievements span across several chapters, they are mentioned in every relevant chapter.

Oil and Water
Complete the oil platform mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

Bogged Down
Complete the swamp mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

Garbage Day! - 1/4
Throw a body into every dumpster you can find.


Throw the body into the dumpster in front of the diner.


Speed Bump
Complete the diner mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

No Sleeping on the Job
Interrupt the gardener's beauty rest.


Keep clicking the door next to the sleeping gardener until he wakes up.


Serial Killer - 1/10
Kill every character that can be killed.


Kill the Gardener with the Broken Fence.


Coffin Flop
Complete the cemetery mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

Garbage Day! - 2/4
Throw a body into every dumpster you can find.


Throw the body into the dumpster in front of the airport


Asset Airways
Check in for your own flight.


Enter your asset number (1080) as the flight number on the terminal.


Body Bag
Complete the airport mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

Damning Evidence
Take a picture of the mine's map after killing the boss.


Kill the boss using the Bird Spikes and take the photo of the map.


Serial Killer - 2,3/10
Kill every character that can be killed.


Kill the Boss with the Bird Spikes.
Kill the Miner in Location 01 in the mine with the Bird Spikes.


Shafted
Complete the mine mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

Fail Fast
Dispose of the body within ten seconds of starting a mission.


As soon as the mission starts pick up the body and drop it in the water.


Serial Killer - 4/10
Kill every character that can be killed.


Kill the Park Ranger with the Machete.


Natural Causes
Complete the national park mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

Journey of Discovery
Become one with the universe.


Accept the drugs from one of the dancers.


Serial Killer - 5/10
Kill every character that can be killed.


Kill the Chef with the Shovel.


Crushed Ice
Complete the mansion mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

Looking for Love
For a bit of Nobodies nostalgia, call Lonely No More Hotline for a good time.


Call number 5388655 (it's the number from the first game).


Memory Error
Forget the elevator passcode so many times that you fail the mission.


Keep calling the elevator support and asking for the code.


Drop the Kids Off
Use the bathroom in Sky Tower.


Use the bathroom on the maintenance floor. It has to be done before dealing with the bungie jumping guy.


Serial Killer - 6/10
Kill every character that can be killed.


Kill the Guard using the Wrench.


Splat
Complete the Sky Tower mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

Garbage Day! - 3/4
Throw a body into every dumpster you can find.


Throw the body into the dumpster right next to it.


Definition of insanity
Keep throwing balls at the carnival game pins.


Keep throwing orange balls at the pins without knocking them down.


Fire in the hole!
Launch the body from the cannon using each weight setting.


Keep shooting the body from the cannon while changing the weight setting each time. Use 75kg as the last one because it's the correct setting.


Collateral damage
Knock down all of the prizes at the carnival game.


Knock down all the stuffed animals using the orange balls, then knock down the pins using the painted metal ball.


Serial Killer - 7/10
Kill every character that can be killed.


Kill the Attendant in the Bottle Toss booth with the Metal Ball.


Toil and Trouble
Complete the amusement park mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

Orange Herring
Keep trying to find a use for the cone.


Pick up the traffic cone from the street, go back to the apartment and keep trying to use it on various things like TV, Dead Body etc. until you get the achievement.


Garbage Day!
Throw a body into every dumpster you can find.


Throw the body into the dumpster in the alley next to the sewer entrance.


Blastoff
Complete the rocket mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

Safely deposited
Complete the bank mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

Excuses, Excuses
Keep making up distractions for the concierge.


Keep talking to the night concierge and asking him to check various situations.


Serial Killer - 8,9,10/10
Kill every character that can be killed.


Kill the Doctor with the Spoon.
Kill the Attendant (Camera Seller) with the Helium Tank.
Kill the Man (philosophing passenger) with the Oar - can only be done after the woman is gone.
If you've killed all characters in the game you should get this achievement now.


Time to eat!
Complete the cruise mission without leaving any evidence behind.


Complete the mission without leaving any evidence behind.

All Clean
Finish the game.


Finish the game.


Hint Hater
Complete the game without using the phone.


Finish the game without using any hints.