I would just go with a Give with one hand, take away with the other approach...

Make it rooted in the game's physical makeup, i.e. For fire resistance, make the player more susceptable to the cold.. so if they want 100% fire resistance, fine, but a cold wind will kill them.

100% Cold resistance, but any heat at all and they start to take serious damage.
100% resistance to Mele, means that movement is severely restricted making them a very slow tank.

If they apply 100% resistance to fire then 100% resistance to cold, then the two effects either reduce to 50% of each or nullify eachother leaving the player completely vulnerable as you can't have immunity to both opposing elements.

If the player tried to get 100% immunity to fire and 75% immunity to cold, then the 100% would cancel out the 75%, possibly making the player 75% more vulnerable to the effects of cold and 0% protected against fire.

Let's face it, when something gets hot and is rapidly cooled, it shatters.
If someone is wearing lots of metal armour to prevent crushing or piercing, they can't move very fast and they're susceptable to electrical attacks, they'd cook inside unless completely shielded.

To defend against electrical attacks, you need plastic which melts and is not as strong as metal armour but good against the cold.

The only thing which is strong and good against fire and crushing with no electrical problems is ceramic which is very heavy and bad at protecting against piercing and cold.

If the player wore plastic underneath their metal armour, it would melt with the heat causing more damage but would protect against electricity.


I think basically, it can be implemented using the physical laws of your world. That way, it seems more natural as opposed to imposing rigid limits which are part of some unseen calculation and give unexpected results.


In Neverwinter nights, the D&D rules get around some things.. Spell casters can't wear armour otherwise they get Arcane Spell Failure, otherwise mages would be far too powerful.. wearing serious armour, summoning creatures and casting immunities to everything.