Redshift Community

In Matras, monsters seem to be unable to enter the city. I tried duplicating the same conditions in my world, but they're still able to enter. I'm aware that I could add doors/gates that teleport the player in and out of my cities, but I'm not very keen on that idea.

Also, are there any workarounds to prevent monsters from following you 20+ squares away? Are there any objects a player can pass through that a monster cannot?

You can't do either, sorry.

In the main game there are certain map coordinates onto which monsters cannot step. These, however, are baked into the program.

Non-NPC monsters will also follow you forever (or until you move out of their sight, which is 7 blocks, you can only do that by teleporting or entering a different underground map). NPC monsters will not leave their map.