I was thinking about this topic the other day as I was flipping through the 4e MM and saw that efreets are totally immune to fire, which suprised me. Fire elementals (to the extent that such a thing exists in 4e) aren't even immune to fire, but efreets are. I considered that they're epic level, so maybe the immunity is warranted. And there are a couple of epic tier options that let one reduce a target's fire resistance... but it doesn't seem like they would interact with total immunity. Infinity - 20 is still infinity. It seems like the epic fire mage would simply be screwed against such monsters.
Yeah, the FFZ alternative might approach this from a few different angles, depending on what the goals for the monster were.
A (use if the monster is rare in the adventure): It's OK for this one monster to be totally immune to fire. Give him an element he takes double damage from, and it's basically a strategy. Because no character will have only attacks that ONLY deal fire damage, even "fire specialists" can do something. It's OK if they can't directly damage the critter, because this is going to be one combat out of several -- most of the time, they can still use their fire damage.
B (use if the monster occurs fairly frequently): Instead of taking fire damage, the "fire damage" the character would have done becomes something else...in FFZ, maybe it becomes MP damage, so while the critter isn't hurt at all, he can't use his powerful mega-attack as long as the "fire mage" keeps up the suppressive fire. Other alternatives might be better, but the fire can still do something.
C (use if the monster is a boss): The monster has a "form" that is immune to fire damage, but a specific strategy will get him to drop this defense. For instance, maybe the monster can use "Flame Shroud" as a defense. He's immune to fire damage, and any physical attack gets countered with a burst of fire. BUT, if the PC's manage to push him out of the pool of lava he sits in, he'll loose that "flame shroud," and you can pummel him with fire attacks (and normal attacks).
You might use "A" if the Efreet Trooper monsters are part of an army of genies at your enemy's command (so fire immunity won't play a huge part in the campaign, just in a few battles). You might use "B" if the Brass Guard Efreet are defending the City of Brass. You might use "C" if the Efreet Pasha boss at the end of the Pyramid of Shadows has become unbound.
You could use all three at once for an extended stay on the Plane of Fire, and even "Desert McFire Genasi the Pyromaniac" would be able to do stuff to as many enemies as "Gravebound Necromancer Vampire Guy"
Oni said:
Of course if you go too far down this road, you go from powers being useless to resistances being useless.
I'd do it by maybe 5-10 points maximum, if you spend a bunch of feats, and then also allowing you to "still" deal 5-10 points of damage against immune creatures, by 30th level, and require that you can only lower one type of resistance at a time. Generally speaking, spending character resources on things that are subject to DM whimsy (like elder editions' Ranger's Favored Enemy) is sketchy, but if your DM is expressly telling you "Hey, iceman, you're in the iceland, there's going to be a lot of things that don't have a problem with ice in their face" by having an extended campaign in a place filled with names like "Winterhaven" and "Coldrock" and "Glacier Peaks" it might be smart, if you STILL want to be an iceman, to take those feats (and maybe not just take everything that deals cold damage).
I mean, realistically, this kind of focus is no different then, say, a PC taking abilities that are ONLY vs. AC, or abilities and ONLY use the axe. Introduce something that has a high AC or something that eats axes, and said character is boned. Personally, I don't think a degree of "forced diversity" is necessarily bad.
To call back the Naruto example, there are basically a lot of "elemental mages," but elemental attacks aren't their only schtick. There's a guy who spits fireballs, and he can do it in a few different ways, but said dude also has Super Ninja Eyes that can read an enemy's moves so he can perfectly anticipate them, and also has a Mutant Tattoo that lets him hulk out into a demon, and also has basic ninja skills like sneaking around and throwing shuriken and jumping through the trees for some reason and minor illusion and evasion tricks, and explosive ninja scrolls....
"Fire" is an important part of his theme, but if he had to beat up a guy made out of fire, it's not like he'd be helpless.
Ice mages work OK in a land of ice, you just have to let them do more than just deal cold damage. Think about what else ice is -- clear, reflective, hard, jagged -- think about things related to ice -- water, snow, biting wind, glaciers -- and generally don't limit yourself to "ice = cold damage."
"So," you ask, "what if the arctic characters move to a temperate or desert zone?" Well, here's where I think we can actually get even more flavor from the deal. Introduce a feat or background bit called "Frostborn" or some such. A frostborn character manifests their personal powers (i.e. spells) with the "cold" keyword to inflict an additional 5 damage, but they also manifest "fire" spells inflicting 5 less damage, even if that brings it to zero. The above modifications for an arctic campaign are really just a shortcut to the same math.
I really like this idea, too.