User blog:Mrob27/The moat experiment



Moat World

As part of my continued exploration of how to deal with Mobs, I decided to dig a deep trench all the way around a large island (hill). I created a new moon for this, in creative mode (explore without limits, safely) and terrain options set to the normal center settings. Some of the techniques from this were later used in my Hollow Hill Project.

I already knew (see this blog article) that you need at least a 5-block-high wall to confine Astronauts for a long time. So I started by digging a 5-block-deep trench around my island:



I eventually dug this trench all the way around the island I had spawned on. It is about 280 blocks long in the east-west direction and about 150 blocks in the north-south direction. The island is a lot bigger than that but I "cheated" by digging through some low parts to effectively make the island smaller.

As I was creating the trench I noticed that astronauts did not always fall in, and giraffes hardly ever fall in.



A giraffe straddles the trench while an astronaut tries to climb out.



A giraffe trapped in a 5-block-deep trench.

Based on observations of astronauts in various types of open pits I knew that I needed an overhang above the trench walls to prevent astronauts from climbing partway up and then jumping out. So after the trench was dug all the way around the island, I deepened it one block and made most of it wider, leaving the top only one block wide:



Completed moat, undercut to make escape more difficult

The moat became so full of astronauts that I decided it would be a good idea to clear them out by adding deeper pits. I placed most of these on outside corners, with a few stepped levels before the main pit, which itself also has overhangs.



The corner-trap viewed from the main trench



Looking down into a corner-trap with about a dozen Astronauts.

Astronauts know where other Mobs are even if they shouldn't be able to see them. They will try to shoot through solid earth:



Astronauts in the moat firing at a green mob.

The only way I got these guys to stop shooting was to kill the green mob myself.