Dead Horn Coral Block is the grey, stone-textured remains of a Horn Coral Block in Minecraft, formed the moment a live Horn Coral Block stops touching water. Dead Horn Coral Block was added in Java Edition 1.13 and Bedrock Edition 1.4.0 as part of the Update Aquatic, and Dead Horn Coral Block generates naturally inside warm ocean coral reefs and ocean ruins. Dead Horn Coral Block has a hardness of 1.5 and a blast resistance of 6, and Dead Horn Coral Block only drops as an item when mined with a pickaxe — any other tool destroys it with no drop.

Unlike the bright yellow live version, Dead Horn Coral Block never needs water to survive, so builders use Dead Horn Coral Block for permanent grey accents in aquariums, shipwreck scenes, and ruined-reef decoration without any risk of decay. Dead Horn Coral Block pairs naturally with the four other dead variants — Dead Tube, Dead Brain, Dead Bubble, and Dead Fire Coral Block — to build textured, stone-like coral structures. Because Dead Horn Coral Block shares the muted grey palette of stone, Dead Horn Coral Block blends into underwater builds while keeping the distinctive antler-shaped coral silhouette.