Valheim is a survival/crafting game in the vein of Minecraft. You are dropped into a simulated world surrounded by forests and six large quest marker stones, and a raven tells you to slay these six beasts in order to enter Valhalla.
Valheim is built around a cycle of day and night which lasts for ~20 minutes. During the night, visibility is greatly reduced and certain enemy types spawn in greater numbers. The night is also colder, which causes a “Cold” status effect while not near a fire.
Alongside the system of day and night is a system of Weather. Storms will blow in randomly and last for several minutes, or even entire days. Weather systems are dependent upon Biome. Most biomes will get basic thunderstorms, but the cold Mountain biome will get snow instead. Biomes will also affect frequency of weather, with places like the Swamp biome raining much more constantly than the Meadows. These weather systems will also affect the growth rate of crops.
The wind direction also plays into the game, bringing your scent towards or away from enemies, and dictating which direction you may travel in a sail-based boat.
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