Zanbatō (5e Equipment)
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Martial Melee Weapons
A sword as tall as a man or so, between 6 and 7 ft long. The zanbatō is mainly a shock or fear weapon used by berserkers, but is most effective in a role similar to a pike; breaking cavalry charges by stabbing a horse or its rider, or hacking the animal's legs from beneath it, or clotheslining a distracted rider from his saddle. The word "zanbatō" literally translates to "Horse Killing Sword."
When you land a hit with the zanbatō on a creature that is either mounted or is itself a mount, the rider must make a Dexterity (Animal Handling) check. The DC for this ability check equals 8 + your Strength modifier + your proficiency bonus. On a failed check, the rider is forcibly dismounted, and both the rider and the mount are knocked prone.