Overview
Sneak is one of Valheim's character skills, tracked under the internal ID Sneak. Determines stamina drain and visibility from mobs while sneaking. Experience is gained at 0.05 per second while sneaking (+0.45 when undetected within the view range of a creature). At max level (100) it grants -60% initial sneak visibility, -20% light based visibility, -75% stamina usage. Adjust your level from the console with raiseskill Sneak 10 to add 10 points, or resetskill Sneak to wipe it back to 0.
Command Builder
Amount
Increases your Sneak skill by 10 points (max level is 100).
Example Commands
Increases your Sneak skill by 10 points. Max level is 100.
Resets your Sneak skill to 0.
About
Sneak skill reduces stamina drain while sneaking by up to 75% non-linearly, with more noticeable reductions in earlier levels. Sneak skill also reduces your visibility to enemies as follows:
While sneaking, your visibility is based on the light level of your position, represented in your HUD as a small bar under the reticle. This bar fills with white as you are in brighter locations, and lowers in darker locations. This value directly reduces the effective view range of enemies when considering if you are seen by them. For example if that "visibility meter" is filled 80% white, then enemies around you have 80% of their view range when calculating if you're inside it.
While sneaking you make no sound. Sneak considers line-of-sight, but is not chance-based. If the enemy has line-of-sight to you, and you are in their modified view range, they will see you. Enemies do have a frontal view-cone, but it is unknown what are the exact angles, which may vary per enemy.