Artefact Porn Magic Items

So a little while ago, I went to r/artefactporn (sfw, promise) and like, its a bloody treasure trove. Literally. Here are 10 made from posts that were on the (or at least, near the) top of all time.
(Except the scarab, it was there when I first took notes on the list, but its since disappeared. There's another one in its stead. One scarab brooch is very like another. Sort of. For my purposes.)

Blade of the Earth's Blood
Made by particularly Socioclastic Druids from the very blood of the earth

Blades which strike this sword, or armour that is smote by it, degrade in quality quickly. Blades degrade a dice size for their damage, and armour provides 2 less AC than normal. These effects require as many days to repair as the decrease in AC value, or in the decrease of maximum damage result.

It can also rust away solid metal at the rate of 1 square inch per minute.

Furthermore, it has a devastating effect on blood, which seems to be an excellent carrier of its magic. Damage taken from this blade is also applied to the target's maximum hit point value as their blood is disassembled at the core of each blood cell. The maximum only returns at the value of 1 per full day of rest.

The Mightiest of Their Kind, Thundering Across the Welcoming Plains
Carved by the very oldest men, when we still knew the spirits who thunder through the invisible airs that surround us.

As long as you offer the proper gifts to the Bison Kings the statue represents, you will enjoy every success on your hunts for a month and a day, proportional to the magnitude of the gifts offered. As it is sympathetic magic that fuels this, the gifts will not be taken bodily. The curse of the Bison Kings will rest heavily on they who take their gifts however.

Hypistrixes' Stone
Carved by a mighty assassin, who was said to be able slay a man in a single blow of his blade when he wished it.

When this stone is attached to a sword, dagger, or the like, its strange magic takes hold of the weapon's wielder. The wielder can no longer score critical hits with the weapon by normal means. However, they can roll a 'tracking' d20, keep it by their side, and reduce the total on the dice by 1 each time they attack. When they make an attack and the 'tracking' d20 shows 1, that attack is a critical hit. They then roll the 'tracking' d20 again, and continue the process.

The effect is born of a Luck Spirit Hypistrixes bound within the stone. While mercurial and alien-minded, it can be communicated with as all spirits can, and those that can form a friendship with the spirit will enjoy the benefits, as the enchantment bonus of the blade increases, and the size of the 'tracking' dice decreases. It is desperately hard to maintain the relationship for very long, however. Luck Spirits are changeable in the extreme, and even day-to-day their tastes and moods change entirely.

Jorrul's Lament
Grown by Jorrul, the mightiest Alchemist of his time, in the shape and temper of his lover.

No-one now knows why Jorrul was driven to grow this creature, though many have offered many differing explanations. All that can be divined however, is that something went terribly, terribly wrong, and the Homunculus grew to maturity alone and masterless.

Now, it lies dormant until someone with the appropriate knowledge of the sigils and rituals required attunes to it. It serves the one who has attuned to it faithfully and diligently as a normal man with scores of 13 in all of its statistics. It has triple the normal number of HP, and bleeds mercury.

If the attuned owner of the Homunculus should die, and the Homunculus can reach the corpse within a minute of its death, the Homunculus will suck the spirit out of the corpse through the mouth, transposing and swapping spirits. The Homunculus dies in the owner's original body, and the owner now lives within the Homunculus' body. The owner replaces their Physical Statistics with 13s, and lose d4 x 10% of their experience points from the transfer, but otherwise survives the experience.

Finnegal's Sacrement
Written by a small boy in a swamp who stumbled across something he really shouldn't have.

The scroll bears a terrible secret, a deep and mighty facet of the universe, contained and bastardised in writing upon a piece of paper, its edges charred and curling as if scorched by flame. The full power of the Sacrement can never be truly unlocked, but with an hour of study, unwieldy magics can be utilised. If you use the scroll, at the end of the hour of study, make a Wisdom Saving Throw. On a failure, roll a d4 and decrease your Statistics by that amount, in any order and combination you wish. On a success, decrease one of your Statistics by 1. Once you have done that, you may change one word on your character sheet to something that it could conceivably be (ie, you could change your race, or change a potion of invisibility to a potion of Immortaility, but not to a potion of Godhood), or you may decrease a single number as much as you like, or you may increase a single number by 1 (no, you can't pick the place value of the number you change).

You may use the Sacrement more than once, but the time taken to study it doubles with each use, and each time you use the Sacrement beyond the first, the number you must decrease your statistics by increases by 1 if you fail the saving throw. So for example, if this is the third time you use the Sacrement, it takes 4 hours to study, and if you fail the saving throw you must decrease your statistics by d4+2.

Statue of Our Lady Belladona
No-one knows or could ever find out what hands carved this statue, or how they carved it 120 feet beneath the surface of the ocean.

Someone who knows the Rites of Our Fair Lady will know that if you drown a willing victim at the feet of the statue, you will bear the curse of Our Lady Belladona. The curse decreases the Constitution Score of the bearer of the curse by 1 each day, and can never be removed, except possibly by divine intervention. Perhaps not even then. The bearer of the curse will only become aware that they have been cursed once their Constitution Score has been halved by the curse, but they will know no further details of the curse except by magics or one who knows the Rites of The Fair Lady of the Seas who tells them.

Someone who is intimately familiar with the Rites of Our Fair Lady will also know that the curse can be passed on by spitting into the mouth of another person, and having them swallow it.

Safe-Guard Scarab
The amulet was carved from Lapis by an ancient Priest of a Cult of Immortality.

At the bearer's command, the owner of the amulet can command the Scarab to burrow into their flesh and dig out an impurity with unerring accuracy. It can also dig out unwanted thoughts, feelings, sights, sense, whatever you can ask of it. However, the ministrations of the Scarab are not pleasant in the least, and the scars are permanent. Each use of the Scarab reduces your Maximum Hit Points by 1d4, or potentially more depending on the nature of the impurity you request the Scarab to remove.

The Reliquary of Martyr Benedictus - Boxwood
Carved by Benedictus' most devoted apostle to contain his last breath.

The Boxwood is magically airtight, and the breath can never escape unless knowingly released, and even when it is released, the breath is recalled instantly when the box is closed.

When held by someone of the same Faith as Benedictus, they may cast Bless upon themselves once per day as part of any non-spellcasting action they make. They may instead cast Bane upon someone of a differing Faith as part of any non-spellcasting action they make.

The holder of the Reliquary can as an action break the Boxwood utterly, totally releasing the power of the Saint's-Relic within, casting Flamestrike centered on themselves. They automatically pass their Saving Throw against the spell. 

The Walls of Respite - Monumental Walls
Built by no human hands, the stones were raised by the earth at the Elves' request, the barriers put in place by the desires of the dead.

As long as the wall stands, nothing can enter unless invited by something within the walls. No power, living, dead, spirit, elemental, divine, can subvert this law. Not even magical or spiritual possession can trick the walls, nor can even sickness or curses.

Servitor Helm - Helmet
Forged a hundred times by the hands of the desperate in the Wars of High Flames, only six are thought to have survived.

The wearer of the servitor helm gains superior mental protection and bravery, the ultimate willingness to dive into the heart of battle and fight without fear. The wearer gains advantage on all Intelligence, Wisdom, and Charisma Saving Throws they must make, and cannot be Frightened at all. However, they are also loyal to an absolute fault, and in fact if they perceive someone to be their Ranking Commander, they cannot refuse an Order from them by any means at all.