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arXiv · 2505.13638

4Hammer: a board-game reinforcement learning environment for the hour long time frame

Massimo Fioravanti·Giovanni Agosta
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Abstract

Large Language Models (LLMs) have demonstrated strong performance on tasks with short time frames, but struggle with tasks requiring longer durations. While datasets covering extended-duration tasks, such as software engineering tasks or video games, do exist, there are currently few implementations of complex board games specifically designed for reinforcement learning and LLM evaluation. To address this gap, we propose the 4Hammer reinforcement learning environment, a digital twin simulation of a subset of Warhammer 40,000-a complex, zero-sum board game. Warhammer 40,000 features intricate rules, requiring human players to thoroughly read and understand over 50 pages of detailed natural language rules, grasp the interactions between their game pieces and those of their opponents, and independently track and communicate the evolving game state.

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Massimo Fioravanti, Giovanni Agosta. 2025-05-19. 4Hammer: a board-game reinforcement learning environment for the hour long time frame. https://arxiv.org/abs/2505.13638

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