Cosmo's Cosmic Adventure Unblocked — Play the Shareware Free

Play Cosmo's Cosmic Adventure online — free shareware episode Works — shareware Episode 1 runs via DOSBox in your browser

Guide updated July 2026 · Runs via DOSBox + WebAssembly

Cosmo's Cosmic Adventure — Apogee's 1992 platformer, in which a small green alien crash-lands on an unknown planet while looking for his parents and has to climb his way out using nothing but his own suction-cup hands. The complete shareware Episode 1, "Forbidden Planet", is hosted here: click Play and the original DOS game boots in your browser via DOSBox + WebAssembly.

It's remembered for one genuinely clever mechanic — Cosmo can't shoot, so climbing walls and dropping bombs is your entire toolkit, and the level design is built around that constraint.

D-pad: move & climb · JUMP: ctrl · BOMB: alt · ESC: menu

⌨ Keyboard — for menus & name entry

Controls — what does what

Action	Keyboard	Mouse / touch
Move / climb	`Arrow keys`	—
Jump	`Ctrl`	`Left-click`
Drop a bomb	`Alt`	`Right-click`
Cling to a wall	jump into it, then hold a direction	—
Menu / back	`Esc`	—
In-game help	`F1`	—
Sound	—	Use the Sound button under the screen to mute

Play next: Blake Stone Micropolis Rodent's Revenge Jetpack all 44 games →

Cosmo's Cosmic Adventure running in a browser tab via ExeBrowser — Cosmo's Cosmic Adventure running in the browser — no install, no upload.

Runs in your browser tab with DOSBox + WebAssembly — nothing is uploaded. Click the screen to capture input; press Ctrl+F10 to release mouse.

Episode 1 of Cosmo's Cosmic Adventure is Apogee's freely-distributable shareware episode. Episodes 2–3 are commercial and not hosted here. Provenance: /apps/cosmo/NOTICE.md.

Get the full trilogy

Episode 1 plays here free — it's the complete shareware episode. Episodes 2 and 3 were the commercial release:

Cosmo on Steam → Cosmo on GOG →

How it works & what to expect

This is the original 1992 DOS release running in a WebAssembly build of DOSBox. The package is tiny (under 500 KB), so it boots almost instantly. Cosmo's suction hands grab any wall you jump into — hold the direction to cling, then climb. Bombs are limited and mainly for clearing blocked routes rather than enemies.

Playing tips

Jumping onto an enemy's head is your main attack, and bouncing off one gains you extra height — several routes need that. Cling to a wall and wait when something is patrolling below; patience beats speed in most rooms. The green bars in the HUD are health, and stars are the score pickups worth detouring for.

Shareware episode — and the full trilogy

Episode 1 is the complete free shareware episode Apogee distributed. Episodes 2 and 3 were the commercial purchase, and the trilogy is still sold — you'll find it on Steam and GOG as Cosmo's Cosmic Adventure. If you enjoy the episode, buying the full set supports the rights holder.

Frequently asked questions

Is Cosmo's Cosmic Adventure legal to play here?

Yes. This is the official shareware Episode 1, which Apogee distributed freely under its shareware model — the same basis as the Commander Keen and Blake Stone episodes we host. Episodes 2 and 3 are commercial and are not included.

What are the controls?

Arrow keys move, Ctrl jumps, Alt drops a bomb. Jump into a wall to cling with Cosmo's suction hands, then hold a direction to climb. The full control table is under the game.

Why can't Cosmo shoot?

By design — he has no weapon. Jumping on enemies and climbing walls is the whole moveset, and the levels are built around that limitation. It's what makes the game feel different from Keen or Duke.

Does my progress save?

Yes — saved games and high scores persist in this browser between visits, best-effort. Clearing site data resets them.

Can I play on a phone?

Yes, a touch d-pad with JUMP and BOMB buttons appears below the game on touch devices.