Cover provides a degree of protection to a target behind it. There are three degrees of cover, each of which provides a different benefit to a target: Half Cover (+2 bonus to AC and Dexterity saving throws), Three-Quarters Cover (+5 bonus to AC and Dexterity saving throws), and Total Cover (can’t be targeted directly). If behind more than one degree of cover, a target benefits only from the most protective degree.
Hide [Action]. With the Hide action, you try to hide yourself. To do so, you must succeed on a DC 15 Dexterity (Stealth) check while you’re Heavily Obscured or behind Three-Quarters Cover or Total Cover, and you must be out of any enemy’s line of sight; if you can see a creature, you can discern whether it can see you.
Area of Effect. If all straight lines extending from the point of origin to a location in the area of effect are blocked, that location isn’t included in the area of effect. To block a line, an obstruction must provide Total Cover.
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