Minecraft wiki entry for Pointed_Dripstone, associated text: Pointed dripstone comes in two different forms, stalactites and stalagmites. Placing a pointed dripstone between a stalagmite and stalactite without sneaking connects them. It can be waterlogged. Mobs can jump up pointed dripstone as long as its height does not exceed four blocks. Horses and other similar mobs can travel up the same pointed dripstone as if they were stairs.