About
Mittens the Kittens is a pixel-art platformer for one or two players on the same couch. Mittens, a tuxedo kitten, can be joined by Simon, a grey and white tabby. Every cat has nine lives, and in co-op that is nine each, not nine shared: only the cat who falls loses a life, the other keeps playing, and the run ends when both are out.
Both cats move the same way. You run, double jump with a spin, dodge roll under gaps a standing cat cannot fit through, scratch with your claws and throw hairballs. You swim against an air meter that you can always escape if you react, and you take three hearts of damage before a life is lost. Co-op is meant to be the easier way to play, and the game does not make anything harder for a second player.
Levels are grouped into worlds of three stages. The first two end at a food bowl, and the third ends at a boss. Each world adds one new idea that goes into your hands, such as a new way to move through the terrain, rather than another hazard. A map connects the stages, there are three save files, and every stage has bronze, silver and gold target times.
What is in it
- One or two players on one screen, with nine lives each in co-op
- Run, double jump, dodge roll, claw swipe and hairball shared by every cat
- Each world adds one new mechanic that changes how you move through it
- Overworld map, three save files and bronze, silver and gold star times
- Pixel art at 480 by 270, drawn to a fixed palette, with no dithering
- Mittens and Simon each have their own full set of animations
Screenshots
How far along
Playable build, 68 out of 100, ranked 3 of 17 on the progress ranking.
Eight worlds with 24 stages and nine boss fights are built, every boss now uses one simple loop, and an automated player finishes them all with no help and no errors, though people have not yet played the latest changes.
- Playable7/10
On 19 October the latest build cleared all 24 stages with no deaths and beat every boss with no help from the test system, though no person has played these changes yet.
- Core gameplay7/10
All nine boss fights now run on one loop (four hairballs leave the dog dizzy for about three seconds, then a stomp on the head, three times) and the jump grace windows were widened to 0.13 and 0.15 seconds, though nobody has played the new boss loop by hand yet.
- Content8/10
All 24 stages across eight worlds and nine boss fights are built, with set dressing placed in every world and about 40 secret rooms, 37 of which the AI found in its best pass.
- Art and audio6/10
Hand-finished sprites cover all eight worlds, all 17 achievements have pixel art icons, and a second review of all 24 stages from 136 camera spots raised the stage dressing score from 7.6 to 8.1 out of 10 with none under 7, but the new sound levels have not been listened to and the largest boss scored below the art pass mark.
- Stability7/10
On 19 October 13 automated runs, solo and two-cat, went through all 24 stages with 0 errors in every run, and two couch co-op bugs (a dismount that dropped a cat back into Samus's saddle and a second cat stuck in the saddle in 6-3) were fixed.
- Release readiness4/10
Windows builds are produced and the game has an options menu, key remapping, a credits screen and a copyright check with no blockers, but there is no public play link.
Assessed Oct 20, 2026. Based on some documentation and posts. This is the studio’s own assessment and it changes as the game does.
Recent progress
Updates
One loop for every boss, cleaner cat poses, and a fresh look at every stage
All nine boss fights now run on one rule you can learn in seconds: four hairballs, a dizzy dog, a stomp on the head, three times. The day also brought two couch co-op fixes, tidier cat animation and a second full review of every stage's backgrounds.
Two hard spots eased, achievement icons, and the fastest test run yet
An ice rink corridor and a climb in the vet's waiting room got easier, all 17 achievements got pixel art icons, and the automated test runs posted their fastest full run and best two-cat run.
A full run with no help, three real bugs, and a shared screen that stopped cutting jumps short
An automated test run cleared the whole game with zero assists for the first time, it turned up three bugs a player could have hit, and couch co-op jumps no longer stop short at the top of the screen.
Two cats under the AI, retimed medals, and a bin in 6-2
The hidden AI run can now play with two cats under the real couch-play rules and found a co-op spawn bug; medal times were reset from the AI's own clear times.
A safety net that dropped the cat out of the world
A rescue routine meant to free a buried cat was sending a cat that merely touched a wall four units down and out of the level; the day also tightened the AI's helper moves and its fight with the Shop Floor boss.
Nine hidden passes of the whole game, and what the log taught
The self-playing mode ran the entire game nine times in a day, each round of fixes measured against the log, and found cat-inside-the-floor bugs that a person would have hit too.
Show 22 earlier updates
Saves that survive a crash, a 20x test run, and a hostile art audit
Saves are made crash-safe, the self-playing mode gets a fast hidden run that writes a shared log, and every sprite, tile and background goes through a four-critic check for machine-made art.
A bug sweep, fairer bosses, and a sound bank with no water in it
Read-only reviews of the menus, Samus, the bosses and every stage turned up stuck states, a boss that could not be beaten after his intro, drowning in silence, and a menu prompt that erased a save.
Reading the AI line by line, and sixteen sounds that never played
A code review of the self-playing mode found places it could loop forever, and a check of the sound list found that 20 of the game's sounds were never triggered, so whole mechanics ran in silence.
Watch the AI stops following scripts and learns the stages
The mode where the game plays itself for streaming now builds its own map of each stage and plays from that, instead of replaying recorded test scripts.
A full test pass, bosses beaten with player moves, and warp boxes that take both cats
With all the new art in, every stage and boss was run through by script. It found ten real blockers, and the day also fixed how warp boxes treat a second cat and a cutscene that fired at the wrong door.
Every required climb becomes a light tap, and the scenery gets fixed by the numbers
A day of difficulty work across Worlds 1 to 8 (closer checkpoints, more hearts, small steps instead of big jumps), a landing fix for thin shelves, and an art pass that finishes the set dressing for every world.
A sound editor, boss introductions and warp boxes everywhere
The game gets an in-editor Sound Editor for all 163 sounds, an introduction scene for each boss, warp boxes in every world, and a movement fix so riding Samus plays like running as Mittens.
New cats, and the ice that wasn't ice
All five playable cats were rebuilt as 3D models rendered down to pixel art, and the last two worlds now exist. Then a line-by-line read of the code found ice that quit working after the first jump and three stages that could become impossible to finish.
No more dithering
The ordered checkerboard shading is gone from the shared art generators, replaced with interpolated colour ramps and smooth opacity. Edges and pixels stay crisp.
Simon, seen on his own body
The new Molly and Simon art went into the game, ten sheets turned out to have been cut by the wrong rules, and Simon was seen in a real two-player run. At game size he reads as a striped Mittens.
Molly and Simon, all the way
Molly and Simon now have every sheet Mittens has, drawn on their own bodies, and two more physics queries that could not see triggers are fixed. A squash frame that made Simon shrink on impact got caught by a check.
Clay mannequins, and the head that carries a build
Every boss shared one lighting flaw that no individual drawing caused, and one boss passed her own quality gate while looking like a cream blob. Molly and Simon also started getting bodies of their own.
The claw that never hit anything
The claw had never struck a single trigger prop, a measurement that said a lift was short was the thing that was wrong, and an importer was quietly flattening sprite sheets. Plus the wet cat, and a sixth world built in a day.
The physics rate was never the one we built for
Every stage was solved at 120 Hz, and the game had been running physics at 50 Hz the whole time. The same day brought sugar you can pour into a floor, a sewer that flows, save files, and a sound-effect fix that was one missing object.
A guard flag that outlives what it guards
A recompile mid-game could freeze Mittens permanently, and the reason was a rule we had written down wrong. Plus a jump test that had been passing an impossible jump for a fortnight, and a background check that measures instead of trusting the eye.
The rule was written down wrong
Recompiling mid-play left Mittens standing still for the rest of the session, and three fixes failed because the codebase had the underlying rule wrong in about fourteen comments. Also, the full build now builds every stage.
A regression wearing a fix's clothes
Playtesters said the grass slows you down and the climb through it is too hard. The first diagnosis was wrong at every step, the fix it produced would have broken the level's own safety checks, and it was reverted before it shipped.
A walk that was half a walk
Bruiser's walk cycle turned out to be four frames played twice, and his nose was facing the wrong way. Mittens' eyes went green, the dogs got real lighting, and yarn stopped looking like a hairball.
A lawn keeps a record
The second world has its mechanic, its art and a first stage you can walk end to end. Every height in it was measured against the real physics rather than derived, and some of the derived ones were wrong. Later the same day the whole world turned out not to be green.
Silence, on purpose
The placeholder music is gone so the real tracks can go in, which meant teaching a build guard the difference between "off on purpose" and "the wiring broke". And a playtest put Mittens inside solid geometry twice, in a way that makes the collision sweeps unable to notice.
Hearts, and two pads that finally drive two cats
Mittens has a visible health bar at last, the two gamepads finally drive two separate cats, and a ride that could trap you forever now lets go. Three of the day's bugs were the same shape — a write that succeeds and does nothing.
World 1 is a world
Two more stages built, a boss you can now actually reach, and an island overworld that connects all three. Couch co-op went from broken to working along the way.