that is why you should use bone, obsidian, or stone weapons to fight them.

Yup. Though some metals don't rust either, like silver.

Lucky for me, I never encountered these nightmares before. As any adventurer, I love my equipment, and if these little f*ckers would render them useless, I would return with HELLFIRE and make their deaths so slow, that arch demons would sit and watch with delights. No game designer was brave enough to do these creatures in their game as well. Would be such a kick between the legs.

Yeah and it only goes to show that not all threats are life and limb. some are much more devious.

In Baldur's Gate 2 there is a Black Dragon foe, that the player needs to fight, to get a quest item to unlock the end area. Main solution is to find a way to kill the dragon. The side-solution is, that you have a ton of magical items and gold, and offer it to the dragon. If the offer (all of your items and gold) meets a value quota, the dragon will leave the quest item, and leave without as fight...
...and leave you naked before the end fight. I wonder if there is a way to beat an end-boss without all those nice magical stuff you fight all the time for. Maybe shape-shifters like druids, demons, elementals can do the job, but fighters, ranged characters and even spell-casters would be at a serious, if not crippling disadvantage. I guess the BG2 game designers put that Pay2Win option there to make the player think, they can get away without fighting the Black Dragon...just to be stripped naked and helpless before the end-boss fight.
Moral of that story is: Pay2Win is never the way!

Hahaha now that's a lesson more modern gamers need to learn

And Game designers as well! Especially mobile games. I only saw one (Repeating for good measure, ONE.) game, which was, pay us $5 for full-version/unlock the end 10%game forever. And even that only gets you the same levels with the most hardest of challenge, and one ultimate bonus combo to help you beat it. With a connect 3-4-5 puzzle game, this was not a bad thing, since you pretty much beat it at this point. But if you are a competitionist, pay us $5 (essentially, support our efforts.) and enrich your experience just a bit further.
But yeah, I really hate micro transactions, and DLC-s...but not as much as Requires Online to Play stuff like PC'S Diablo 3.
I yearn for the old days, where you buy a game on a cd/dvd pop it in and play it whenever you want it, without the worry to se an advert or a paywall. The old days had paywalls as well, and it was called "Expansion", and you could buy it if you wished to enrich your experience on that certain games. Nowadays, game developers like to take you hostage, and give you part of the game, with some implemented way to make you pay them even more...sad times for gaming indeed. Bring back the offline, complete games era!

you're speaking my language man i'll tell ya.

I mean i do enjoy some online gaming things but just as an example, The Organ Trail does not need online connectivity to run so why does it have it? Leaderbords? That's a load.