Steam game

S.E.M.I. – Side Effects May Include...

S.E.M.I. is a single-player and co-op action platformer with puzzle elements. Play as patients of an unusual clinic, take experimental drugs, interfere with each other, and be ready for chaos and unpredictable side effects!

$7.99 January 23, 2026

By Two Horn Unicorn

Windows Controller: full
View on Steam
S.E.M.I. – Side Effects May Include... - Two Horn Unicorn. Popular. Released January 23, 2026
Screenshot of S.E.M.I. – Side Effects May Include... gameplay showing in-action mechanics Screenshot 2 of S.E.M.I. – Side Effects May Include... - additional gameplay view Screenshot 3 of S.E.M.I. – Side Effects May Include... - more gameplay footage Screenshot 4 of S.E.M.I. – Side Effects May Include... - final gameplay screenshot

Overview

About this game

S.E.M.I. is a cooperative online game about escaping from a special clinic. Here, you and up to 3 of your brainless loyal friends play as patients, fighting staff and other patients while stumbling into all sorts of unexpected situations. Brawls, side-effect pills, and brutal platforming will absolutely challenge your clumsy friends’ hands sense of teamwork. Expect obstacles, puzzles, deadly traps, and rooms where a single wrong move can knock out the entire squad.

Communicate in voice chat and arrange sabotage help your friends pass through rooms, get out of traps and fight with opponents! In your arsenal: close combat, physics, amazing abilities and ... imagination!

Take pills and get abilities:

  • Bipolar force is an invulnerable monster, then a helpless rag!

  • Laser astigmatism — two sights, one laser… Where will he shoot?

  • Stendhal syndrome — are you looking at a painting? Now you're hysterical and destroying everything around you!

  • Alice's syndrome is either tiny or gigantic — have time to adjust!

Madness is near! You and your friends can go crazy and start running, jumping and fighting, and your abilities will become uncontrollable. Do you want to take back control? Take the pills :)

Locations are randomly generated from rooms with changing gravity, traps, moving walls, and other "pleasant" surprises.

After a successful escape, you will receive a medical report: "The patient was stable until he started hitting the guards with a bottle. Diagnosis: Overmotivation" or something worse!

Unlock new costumes and decorations. Let each new escape be more stylish than the previous one!

Will you and your friends be able to escape... or at least not go crazy?

Welcome to the mental hospital! Here, your abilities are a lottery, and your friends can be the most dangerous opponents!

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