Regarding reecap items, apparently they can adopt features from people they kill when they dye their caps in their blood. So perhaps a magical item based on that idea? Like a hidden feature of that armor that if it's stained with blood of a murderer you have killed you'll start adopting their features, kind of like how you mentioned changes during fey contracts. Don't tell the player why, just tell them that they've started changing while they're attuned with that armor and punish then if they don't follow that cursed new personality till something changes, like them un attuning or something. And it's not just personality features, but any feature of the murderer is potentially up for grabs, including racial features, special abilities etc. Perhaps if enough bloodetains are accumulated you could give the players a hint by changing the rarity of the armor. If they wash the blood away just remove the features till the next blood stains are added etc. But the blood stains *have* to be from a murderer, not from a random urchin or rat or whatever who has never killed before. The player killing someone innocent won't trigger this hidden feature. Features could include cool things like adding a dragonborns breath weapon attack too btw. Anything that the DM deems appropriate given the recaps lore and the murderer whose blood is the source of the stain and the story. It shouldn't be too OP, nor too upsetting to the player. If it changes their personality let them know that it's not permanent in OOC, but that they need to figure out why themselves. End of video: Regarding the Eladrin chainmail. Remember that it's also their nature to change a bit with the seasons. So you could have the resistance types change at times and still fit the theme. So perhaps keep the current list of residences, but occasionally switch a random one out with elemental protection depending on the season or players mood or the next planned encounter you as a DM are planning and worrying about being too hard or whatever. But only if they feed those hit dies.
