Prime Artefacts are pure artefacts that seem to originate from a time and space even before the world as we know it even came to existance, as described by Galthen in his book about them.
The Artefacts known are all related to strange events that have happened or are still happening in Tibia. Known Prime Artefacts are:
Ring of Ending: Broken Rings of Ending come from Another Dimension and, when combined with a String of Mending from the nightmarish Roshamuul forms the complete ring - or kills ther person who was trying to do that.
The True Book of Death is a tome protected by the leader of the Deathlings, Brokul. The Deathlings are creatures which evolved from Deeplings and became stronger while seeminly bowing to dark forces.
The Spatial Warp Almanac is also a tome, guarded by the Order of the Falcon's leader, Grand Master Oberon. The Falcon Knights were afflicted by some sort of curse after an excursion to Zao, and the Almanac could be related to it. The Almanac can also be used as a magical key that teleports you to a weird part of Another Dimension where apparently all the misplaced Parcels of Tibia end up.
The Supreme Cube is an artefact which was of great importance to the Planegazers, and some information about it can be learned from their headquarters. An incomplete Cube was carried by the Last Planegazer, but its Missing Part can be found hidden inside Galthen's grave. The Supreme Cube is also another dimension itself, and inside it it's possible to meet the Planestrider.
The Cobra Amulet is an artefact recovered by Scarlett Etzel in a nameless crypt, one that allows her to see through the material plane into infinite distance as described in The Order of the Cobra Compendium. The Amulet can be sacrificied in a ritual to reverse everything that happened to Scarlett and Galthen, as written on the Note About Two Souls.
Megasylvan Sapling. A Sapling of Megasylvan Yselda, it's the prime "Seed of Life". Yselda was the betrothed of Kesar the Younger, King of the Order of the Lion. She was victim of a curse which transformed her into a Carnisylvan, an organic mammal, sentient and intelligent but belonging to the realm of beasts but also are inherently human and are probably conscious.
The Living Idol of Tukh is a small statuette, similar to Golden Idol of Tukh.
Besides the 7 known Prime Artefacts, there are 7 Cloth Fragments sold by John, carpenter of Bounac, which clearly depict images of the Artefacts. Each carpet becomes a different coloured carpet when used on the corresponding artefact:
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Two of the Cloth Fragments show the "incomplete" versions of the Artefacts (The Cube and The Broken Ring of Ending), which suggests whoever created them did not find their missing pieces. It's hard to say if it shows The Cobra Amulet or the Note About Two Souls, since both share the same Snake shape. In this case, however, one could consider that only the Amulet is an Artefact, not the Note, even though it's still magical and contain some of the artefact's "essence".
Galthen is known to have done research about the Arfetacts, and is also directly related to three of them. He died in possession of a part of the Cube, his love story with Scarlett led to the discovery of the Cobra Amulet and he explored the Forest of Life seeking information about Yselda. During his explorations, he built an Artefact Box to safely store them. He also ventured inside the lost city of Iksupan, where Ahau resides and is in possession of The Living Idol of Tukh.
Some of the Artefacts are related to the Ancient Orders of King Xenom, but why all the Orders found the Artefacts (or the Artefacts found the Orders) is unknown. Two of the Artefacts are keys to finding the entrance to the Secret Library, where Variphor schemed to steal the ancient knowledge of Zathroth about The Godbreaker. The Godbreaker is a weapon created ... in the most heated phase of the godwars by Zathroth's own raging son, to kill his godly opponents once and for all, but it was taken away by Zathroth and imbued with incredible enchantments and magics, never dared to be used before or later.. Its pieces were in possession of Ferumbras, but they were stolen by Variphor's minions.
The Deepling and Deathlings races also appear more than once in connection with the Artefacts, as do the mysteries that surround Roshamuul, which was likely created by the actions of Variphor.