I've been thinking about this for a while. It would be convenient, for my specific purpose and perhaps for someone else's, to be able to choose, specific to each mob, which ones are passive, aggressive or neutral. I had the idea because I'm trying to start a realistic-ish underwater survival/freebuild, and for that I've added Karl-Alfons' KaDiving, but I was thinking that would make the game too easy(being that there aren't any creepers/zombies/skeletons underwater). So I was thinking of making squids aggressive(Yes, it sounds a bit ridiculous). It doesn't sound like something under high demand, but even if it was a simple config.yml file, that would be enough for me. If you are willing to also add a few commands, that could also be useful. Something in the likes of; /MManager Toggles between default minecraft properties and custom mob properties(according to config.yml/last saved mob properties), essentially Enable and Disable /MManager [Mob_Name] [Passive/Aggressive/Neutral] Maybe even; /MManager [Peace/Chaos] Peace causing all mobs to turn Neutral, and Chaos causing them to turn Aggressive. If anyone's interested in coding something of the sort, let me know. PS: I know nothing about coding or java, so me saying that a config.yml is simple is probably obnoxious, but I hope someone with the interest in this idea will understand my lack of java knowledge. PPS: If anyone thinks "CrowdControl", the plugin's been inactive, so that's a no. PPPS: It could be called "MobManager", as I used in this thread. Just a suggestion.
Can already be done with CustomDifficulty. If you can make it so we can make mobs hostile to other mobs (by type), then you'll be achieving something