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. If behind more than one degree of cover, a target benefits only from the most protective degree.
Cover
Benefit to target
Half Cover
+2 bonus to AC and Dexterity saving throws
Three-Quarters Cover
+5 bonus to AC and Dexterity saving throws
Total Cover
Can’t be targeted directly
Hiding behind cover. With the Hide action 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.
Areas of effect. If all straight lines extending from an area of effect’s point of origin to a location in the area 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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