What needs to be imagined now is every type of damage in a fantasy role-playing setting. Sure, many of much I am about to list could be condensed, simplified, and cut down. However, that's what you do after you list all the brainstorming. In fact, if you have any more suggestions, go ahead and mention them. If you think anything on this list should be collapsed, eliminated, or simplified, you can mention that too.
Here goes:
Damage from weapons can be divided into piercing, slashing, and bludgeoning.
Damage can also be divided up by four elements, such as Earth, Fire, Wind, and Water.
Magical Damage can be divided up into Arcane, Shadow, Necromantic, Electric, and Frost
Other types of damage could be Biological, Acidic, Poison, or the broad Nature
Finally, there is always Holy damage.
Now, I already think that many of these can be collapsed. Some can be gotten rid of. However, every conceivable type of damage should be covered and then people can turn on the left brains and cut things out.
Please, tell me what you think of the list and add, remove, adjust etc as you see fit because that is an important step before listing off abilities of characters.