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