Pen Apple

What it does

Pen Apple is a roguelike deckbuilder where AI crafts the fun, chaos, and stories. The game uses Gemini to dynamically generate and interpret in-game content, especially the cards. Instead of pre-programmed logic, natural language descriptions serve as the “ground truth” for Gemini Flash to determine card effects. This enables zero-effort creation of complex actions like “Anagrammer,” which transforms all cards into their anagrams
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We’ve moved beyond traditional procedural generation, using LLMs to guide content creation. Gemini Flash designs the lore, enemies, loot, and rewards, capturing the spontaneous gameplay and accidental absurdity of classic roguelikes and early interactive fiction.

“Generation” has always been central to roguelikes and video games, rooted in tabletop RPGs where a game master crafted stories. As RPGs transitioned to video games, procedural generation emerged to replicate this improvisation. While games like Dwarf Fortress have taken procedural generation to new heights, LLMs offer a more natural way to create emergent gameplay. In Pen Apple, we fully embrace Gemini as the primary content generator, leveraging its long context window for deeper storytelling.

By using a retro game engine, we evoke the charm of the earliest roguelikes while showcasing the cutting-edge capabilities of Gemini Flash. Ultimately, Pen Apple aims to capture the fundamental fun of games through wordplay, chaos, and emergent narratives.