7 Best 13KB Open-Source Games to Play Now

Long time no open-source game roundup!

Today, we’re diving into the winning mini-games from the 2024 and 2023 editions of the js13kGames competition.

For those unfamiliar, js13kGames is an annual web game development challenge where participants have just one month to create a browser-based game—under a strict 13KB size limit. Here’s how it works:

• 13KB Size Limit: The submitted game (in a ZIP file) must not exceed 13KB, including all code and assets.
• No External Dependencies: External libraries, APIs, or resources are prohibited—everything must be self-contained in the ZIP.
• Entry File: The ZIP must include an index.html—players should be able to unzip and play immediately.
• Open-Source Encouraged: Participants are encouraged to share their code on GitHub.

Url: js13kgames.com

Every year, the Js13k competition delivers a treasure trove of quirky, creative mini-games. Now, let\’s dive in and play some of the most mind-blowing entries from the past two years!

The 2024 theme – \’Triskaidekaphobia\’ (the irrational fear of the number \’13\’) – inspired developers to cram their darkest numeric nightmares into just 13KB. Let\’s explore these micro-sized horrors.

During exploration, you may activate your flashlight (press F) to illuminate your path and locate items. However, when the creature emerges, exercise extreme caution: immediately deactivate your light source to remain undetected, or rapidly seek concealment. To optimize the terrifying experience, we strongly advise using headphones – just be warned, you might need to change your pants afterward!

Gameplay Tips:
While exploring, you can use your flashlight (press F) to light the way and search for items. But when \”It\” appears—be careful! Turn off the flashlight to avoid detection, or sprint to find hiding spots. For maximum immersion, we recommend wearing headphones… though be prepared to get scared!

Controls:

• Movement: WASD
• Look/Turn: Mouse
• Interact: E or Left Mouse Button
• Flashlight: F

Play Demo: https://play.js13kgames.com/13th-floor/
Source Code: https://github.com/js13kGames/13th-floor

The dice \”cargo\” is your lifeline—the sum of all dice faces determines both your total HP and attack damage. But beware: rolling the cursed number 13 will bring dire consequences.

Links:

• ▶  Play Demo: Coup Ahoo
• </> Source Code: GitHub

Controls:

• Move: Arrow Keys (↑ ↓ ← →)
• Pause: ESC or Enter
• Restart: R
• Undo: Z or Delete

Links:

• ▶  Play Demo: Ghosted
• </> Source Code: GitHub

2023 Theme: \”13th Century\” – A Nostalgic Knight\’s Tale
Step back into the age of chivalry as we explore the most captivating mini-games born from this medieval challenge!

A masterfully crafted fighting game with incredibly satisfying combat mechanics. You play as a lone soldier battling through relentless enemy waves—until the ultimate boss makes its grand entrance.

Rich Game Details:

• Water slows movement, while dynamic weather (wind/rain) and swaying grass heighten immersion.
• Kill-cam slow-mo delivers epic combat climaxes.
• Fog-of-war vision creates perfect roguelike tension for this 2D hack-n-slash.
• Every element conspires to make you crave \’one more run\’.

Links:

• ▶  Play Demo: Path to Glory
• </> Source Code: GitHub Repository

A delightful casual game where you strategically place land tiles to create paths across the map—while collecting loot to upgrade your deck! Discover powerful skills along the way to spice up your adventure!

• ▶  Play Demo: Casual Crusade
• </> Source Code: Github Repository

An endless 2D action runner with a hilarious helicopter helmet twist! The rules are simple: collect gems and keep moving—just don\’t stop!

Controls:

• Move: ← → or A/D
• Jump/Fly: ↑ or W
• Spear Attack: Space
• Pause: Enter

• ▶  Play Demo: Knight Dreams
• </> Source Code: GitHub

2.4.Tiny Yurts

A casual strategy game inspired by Mini Motorways, blending pathfinding with resource management. Simply click-and-drag to connect yurts and farms, creating happy habitats for your animals. Easy to learn but endlessly engaging—give it a try!

Game Mechanics & Pro Tips:

• ▸ Pause & Plan
  The game supports pausing at any time—use it to optimize your routes strategically.

• ▸ Flexible Start
  You can delete the pre-built paths from your starting farm to redesign the layout freely.

• ▸ Water Challenges
  Water blocks can\’t be built on—connect fisheries using floating bridges instead.

• ▸ Distance Matters
  Shorter paths improve efficiency. Plan wisely to meet farm demands effectively.

• ▸ Lost Settlers
  If settlers get lost, rebuild their path home before they can work again.

• ▸ Diagonal Shortcuts
  Diagonal paths save space but increase travel time—use them thoughtfully!

• ▸ Growing Complexity
  Different animals have unique needs, and difficulty scales as you progress.

Play Now: Tiny Yurts
Source Code: GitHub

With that, we’ve unboxed all 7 open-source mini-games for today! It’s truly impressive how much creativity and polish these developers achieved under the brutal 13KB constraint.

Which game blew your mind? Was there one you couldn\’t put down? Or did you spot any genius design/tech tricks in these 13KB wonders? Share your thoughts in the comments—let\’s geek out over these tiny miracles together!