Toward More Plausible Mob Behavior

For me, changing the appearance of mobs isn't enough to give me the perception of a well-realized animal ecosystem in a game world. For whatever reason, the appearance of a thing is less interesting to me than the behavior of that thing. Sure, I prefer pretty over ugly; it's just not what matters most to me.

So I don't get too excited by the occasional developer suggestion for changing the appearance of a mob (whether a creature or an NPC) based on that mob's age. It would be a minor addition to the worldiness of the game, so I wouldn't object to it, but it wouldn't excite me.

What would excite me would be if the behavior of a mob changed according to the maturity of an individual mob, the normal intelligence level for that type of mob, and the environmental conditions.

Assuming a world with Juvenile, Mature, and Aged versions of a mob, it's fun to imagine them displaying different behaviors in different circumstances. Maybe something like:

	NORMAL	THREATENED	ATTACKED	INJURED
Grazer
Juvenile	play	run to parent	defend	escape
Mature	graze/patrol	defend	defend	escape
Aged	rest/graze	defend	escape	escape
Predator
Juvenile	play	investigate	defend	escape
Mature	rest/patrol	attack	attack	escape
Aged	rest	defend	escape	defend
Semi-intelligent
Juvenile	investigate	attack	run to parent	escape
Mature	patrol	attack	attack	defend
Aged	rest	defend	attack	escape
Humanoid
Juvenile	play	investigate	run to parent	escape
Mature	patrol	investigate	attack	defend
Aged	rest/patrol	defend	defend	defend

(Note that this is primarily for combat interactions. For other kinds of activities, semi-intelligent and intelligent mobs -- NPCs -- would have other tables for generating other kinds of reactions in other situations.)

If distinctive behaviors like these were implemented (especially with a little bit of randomness, and with the ability for members of groups to signal their states to each other), the game world would feel vastly more dynamic.