Fever Swamp - Rules of Play says:
The air is moist. The moisture mixes with your sweat — the heat is relentless. The drone of insects gives you headaches, and the fever from the infected wounds has left you delirious. Your raft is damaged, and there are spirits in the trees. You’ve only been here for three days. Fever Swamp is a hex-crawl sandbox adventure compatible with Lamentations of the Flame Princess and most other Dungeons & Dragons clones.