Are undead resistant to bleeding? Do dermapteran fear fire? Cold against human a good choice?
To answer these and more questions regarding actual resistance, weakness and other quirks about foes, an in-game bestiary would be, not only useful, but rewarding at the same time. Some ideas:
The bestiary would be accessible, using its own window, right from the start much like other information windows (Factions, Quests, etc…)
The bestiary would be, much like blueprints, cross character/account global. i.e: Any character can contribute toward expanding it and also access already unlocked information.
At the beginning of the game, it would be blank. As you kill enemies, it would start to fill up.
Only enemies killed during the traditional main story progression would count toward unlocking more information in the bestiary.
Some levels of information, tiers of some sort if you will, could be devised. Example: After killing ‘x’ amount of “Reanimators”, you get to unlock that enemies “portrait”. After ‘y’ amount of kill, you get to learn it’s basic attributes. After ‘z’ amount of kills you can view its resistance and weakness, and so on and so forth for other informations possibly including:
A more advanced controllable 3D view.
A description of the current tier of information you have access to. “You are a ‘Reanimator’ neophyte.” or “You are an expert on ’ Dermapteran Sentinel’.”
Possible player attack or defense bonus against an enemy you know a lot about. This could be implemented just for ‘heroic and special boss foes’.
Information on where that particular enemies might be found.
Information on what that particular enemies ‘drops’ are.
Much like experience points, unlocking more information in the bestiary would require killing enemies that are “dangerous” to you. i.e: Killing level 5 enemies when you are level 44 would not count toward advancing the bestiary tiers.
I think this would help a lot with immersion as well as learning more about what can be effective against a foe without having to Alt-Tab out of the game to check on the internet…