Multi-agent training for Pommerman: Curriculum learning and population-based self-play approach
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Abstract
Pommerman is a multi-agent environment that has received considerable attention from researchers in recent years. This environment is an ideal benchmark for multi-agent training, providing a battleground for two teams with communication capabilities among allied agents. Pommerman poses significant challenges for model-free reinforcement learning due to delayed action effects, sparse rewards, and false positives, where opponents can lose because of their own mistakes. This study introduces a system designed to train multi-agent systems to play Pommerman using a combination of curriculum learning and population-based self-play. We also tackle two challenging problems when deploying the multi-agent training system for competitive games: sparse reward and a suitable matchmaking mechanism. Specifically, we propose an adaptive annealing factor, based on agents’ performance, to dynamically adjust the dense exploration reward during training. Additionally, we implement a matchmaking mechanism utilizing the Elo rating system to pair agents effectively. Our experimental results demonstrate that our trained agent can outperform top learning agents without requiring communication among allied agents.
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© 2026 The authors. This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License.
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