Erosion

About this board game

Erosion is a board game for 2–5 players, with games lasting about 30 minutes, in which you uplift your mountain by eroding those of other players.

At the end of each round, you gain points for the cards in your mountain and delta. The basic rules focus on four player actions, giving each turn a clear connection to the geological processes that shape the planet.

• Weathering: Break down rock through processes such as crystallization.
• Hillslope: Transport weathered material using movement such as creep.
• Fluvial: Move eroded material through the River toward the sea.
• Draw Cards: Add new possibilities to your hand.

Water catalyzes almost every step of erosion. After rock is weathered and transported to the River, it moves as sediment toward the sea. Braided rivers carry the maximum sediment load, but they are also the least stable and the trickiest to play.

Advanced rules add atmospheric change, ice ages, glaciers, flood volcanism, quakes, and other details. These systems reflect how mountains act as immense terraformers and greenhouse gas scrubbers: weathering removes oxygen and carbon dioxide from the atmosphere, while major flood volcanoes can return vast quantities of carbon dioxide.

With its geological theme and connected mountain, river, and delta processes, Erosion presents Earth’s dynamic cycles on a six-million-year game scale. The 2009 game turns the growth and death of mountains into a compact contest shaped by weather, transport, and planetary change.