Diet: Roots and worms
Lifespan: 16 years as grub, 1 month as adult
Long tracks of the great plains of our world are barren, paths through the grasslands wide enough for a wagon. Those visiting these lands of tall grass for the first time may mistake them for manmade paths through the wilderness, but they are, in fact, natural, created by the massive grubs below the earth. They eat the roots of the plants they squirm under, killing the plant above and leaving barren earth until the next seeding season. In regions where these beasts are common, fences are staked deeper in the ground and reinforced with wards that drive the grubs away, lest they devour crops.
These grubs are the juvenile form of the mighty shoguntaur. Every 8 years, they emerge en mass from the earth and metamorphosize into their adult forms. In this form, they lack a mouth, relying on stores of fat from when they were feeding as grubs underneath the ground. For the last month of their life, they roam the surface, making a general menace of themselves. They joust among themselves for access to prime laying around and mates, fights that often end up fatal for one or both parties. More important than this, they easily mistake humanoids, especially mounted humanoids for members of their own species.
When faced with a threat or a rival, a male shoguntaur starts with an aggressive display. It prances back and forth, showing off the length of its lances, horn, and tail, its primary weapons. If a male finds that his weapons are significantly shorter than those of his opponent, he will usually retreat at this point. If neither backs down, they will joust, charging at one another. Normally they will make a few clashes before one runs away or is killed, but when faced with an opponent who does not fight like a fellow shoguntaur, they aggressively stab with both lances and their horn and lash with their tail, becoming a relentless force of violence, although one not particular resistant to damage itself.
Some unhinged knights have found ways to extend the lifespans of these creatures, gaining themselves wild but powerful mounts, although stopping them from attacking other cavalry in your own army is a trick few have pulled.