Here is the full list of all 84 OMORI achievements. It takes around 80-100 hours to unlock all of the achievements on Windows.
Receive all FLOWERS in the hospital.
Unlock all achievements. Thank you for playing OMORI.
Insert every song into GINO'S JUKEBOX.
Feed the STRAY CAT every day and sunset.
Go to SEAN and KAREN's housewarming party.
Defeat the RECYCLEPATH.
Give FLOWERS to MARI.
Battle the "bees".
Defeat the HOOLIGANS with PEPPER SPRAY.
Take $20.00 from KEL's wardrobe.
Quit in the middle of a part-time job.
Get a perfect score delivering PIZZA.
Defeat the PET ROCK champion.
Don't high-five KEL.
Lose to KIM and VANCE.
Complete the grammar worksheet correctly.
Complete the math worksheet correctly.
Reach the other ending.
Complete the FOE FACTS! journal.
Read all the tombstones in the... dev room...
Commission all of GATOR GUY's statues.
Throw away something.
Beat the BOSS RUSH.
Defeat MUTANTHEART.
Defeat PERFECTHEART.
Defeat the CHICKEN? at the top of DINO'S DIG.
Recover at all of MARI's picnics.
Take the KEEPER OF THE CASTLE's power.
Visit all mirrors.
Defeat every SOMETHING at the bottom of the LOST LIBRARY.
Defeat SPACE EX-HUSBAND.
Look through all telescopes.
Let the plastic fish finish its song.
Defeat PLUTO and THE EARTH.
Get the FLOWER CROWN from BASIL.
Complete your TO-DO LIST.
Pet all the creatures in MARINA's sector in HUMPHREY.
Defeat ROBOHEART.
Choose the WINTER MOLE.
Choose the FALL MOLE.
Choose the SUMMER MOLE.
Enter code: haveadollariguess at www.omocat-shop.com for $1.00 off.
Get all rewards from the RECYCLING MACHINE.
Reach the bad ending.
Commission all of ROCOCO's art.
Defeat 100 BUNNIES.
Defeat 100 SQUIZZARDS.
Hold 99 TOFU.
Trade CLAMS for CLEMS.
Watch all movies in SWEETHEART'S "throne room".
Have a ghost party.
Complete ORANGE JOE's quest.
Reach the good ending.
High-five KEL three times.
Brush your teeth every day.
Defeat HUMPHREY.
Defeat SLIME GIRLS.
Get the LOL SWORD.
Defeat UNBREAD TWINS.
Commission ROCOCO.
Turn the valve to the right in RAIN TOWN.
Defeat PLUTO (EXPANDED).
Defeat MR. JAWSUM.
Defeat SWEETHEART.
Kill the first SOUS CHEF.
Perfectly train the SPROUT MOLE choir.
Ruin Christmas.
Choose the SPRING MOLE.
RELEASE ENERGY on your foes.
Go to sleep after a long day.
High-five KEL.
Complete all part-time jobs once.
Wake up in the morning.
Defeat SPACE EX-BOYFRIEND.
Defeat DOWNLOAD WINDOW.
Listen to MR. SCARETHROW's rant.
Defeat THE EARTH.
Defeat KITE KID.
Pet a dog.
Make your way and talk to LONE MOLE.
Gain BREAD using BREAD SLICE.
Defeat ???.
Fly the BUTT CERTIFICATE in CATTAIL FIELD.
Water a plant back to life in BASIL's garden.