Lanternlake

Lanternlake is a cosy idle fishing game with one gentle twist: catch and release is an investment.

Every fish you reel in shows its size, weight and coin value, plus a growth curve to its maximum size. Keep it for coins now, or let it go: released fish keep growing in real time (even while the game is closed) and may come back bigger and worth more. Release two of the same species close together and a new generation can hatch, with a small chance of a rare colour for your field guide. It is a fair, readable bet, never random money.

Free demo (play it in your browser above)

Willowmere Pond, the whole first lake: all 12 of its species, the reel mini-game, the first levels of every upgrade, three helpers who fish on their own docks (with rules you set), growing and breeding fish, the field guide, daily wishes and 34 of the 38 milestones. Your progress is saved in your browser.

Full game (download)

• 3 lakes: Willowmere Pond, Cloudveil Lake (mountain rain) and Lumenhollow (full moon and rare night fish), each with its own music and weather
• 36 species, each in four colour patterns to find, with a silhouette for every fish you have not met yet
• Every upgrade level: rods, reels, lures, bait, boats, a roomier bucket, helper tea breaks and the lake hatchery
• Five helpers with catch rules (keep everything, release growing fish, or keep anything under X coins)
• Offline progress: your helpers keep fishing and your released fish keep growing while you are away (up to 12 hours), with a "while you were away" summary
• 38 milestones, daily wishes and a statistics page
• Plays offline: unzip and open index.html in your browser. No ads, no purchases, no account

Controls

Mouse or touch: hold Cast a line and let go to cast, tap Hook now! when the bobber dips, then hold Hold to reel to raise the line tension and let go to ease it. Keep the needle in the green.
Keyboard: hold Space to cast, press Space to hook, hold Space to reel. P pauses (it opens the settings page); P or Esc closes it again.

Built with AI tools (ChatGPT and Claude), then reviewed and polished. Music, sounds and art are generated in code.

Make your own

This game was built with Codex in ChatGPT from our Idle Fishing Game Builder prompt on PromptBase, then reviewed and polished for release. Use the same prompt to build an idle fishing game with your own theme.