Current questions and answers regarding the map editor.

Guys, can you tell me how to create chasms in the Dungeon?

If you mean how to burn out the Dungeon itself, to create free space there, then use the Lower tool in the Tiles tab. Be sure to set it to a value of 3 and burn it out. To make sure you can see something, in the map settings, in the general map properties, there is an ambient light for underground setting. Set it to something that isn't underground (for example, Haven Light (Grass)). After you finish the map, set it to any light, preferably an underground one. Otherwise, if you have sunlight underground, it will look, to put it mildly, strange. In general, everything is written in the manual.

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If you mean something else, explain it more specifically.