When the Avatar dies, he loses some exp and get's respawned to a default area. Monsters can walk in some AI manner. Some can walk in straight lines, some walk in a random manner, and others will walk toward the Avatar, either in an aggressive or docile manner. The key to generating levels is having a good imagination and a straight heads up on linear vs. parallel quests. Generating NPC's is simple as clicking and typing the name and stats.
Triggers are as easy as point, click and type the info.
Check the source out. I may one day redesign this game for 3D, but that's still in my imagination. I do not play any online games anymore, since I am very busy programming, but that may change when time becomes available, or when I stop updating this project. I have the feeling I would like to make more games in 2D, but I think this Ultima project is the final chapter. I did make a copy of U4 many many years ago when I was 17 with Atari Basic.