Boivindo

The creature picks one target within 64 blocks of it, chosen from the player who has the most hunger, saturation and meat eaten. Beef, pork, mutton and chicken all count toward that score, and the tally is kept across sessions. Every other player is treated as a threat only when they come close. The monster walks at a fixed speed and turns its head toward the target, but it does not need line of sight, and it tracks the target through stone.

Walls and closed doors only slow the chase: it opens doors, takes longer routes and arrives anyway. Hiding cannot make it lose interest, and a boss bar with chase music signals that it is hunting. Hitting it enough knocks it down for about twenty seconds before it stands back up at full health, so damage buys time and nothing else. The mod is published for Fabric 26.2, runs on client and server, and needs Geckolib.