Feather of Aethon (5e Equipment)
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Wondrous item, unique
As Celestial Phoenixes are all but extinct, the only way to get a feather of one is by Aethon Sol, the last surviving member of the species. This doesn't necessarily mean you have to take it by force, as sometimes the bird will give one to those he cares about. And, he, ya know, also sometimes sheds them. As ya do. Because of this, they've come to be known as Feathers of Aethon in some circles, though sometimes they do have simpler names like Phoenix Feathers.
You don't age or suffer the effects of old age while this feather is on your person (And are immune to the effects of cold weather). Additionally, while this feather is held in your hands you are resistant to cold damage. You are instead immune to cold damage if you are already resistant to it without holding this feather. The feather emits dim light out to a radius of 5 feet.
You can use your action to produce a spell effect identical to the true resurrection spell. Doing so destroys the feather. If the feather is on your person when you die, the feather destroys itself at the start of your turn and casts the true resurrection spell on you instead. In either case, the target of the effect reappears in a blast of light and fire that deals 8d6 fire damage to creatures of their choice within 5 feet of them (which can be made to include no creatures, making a harmless but still very present explosion).