The Golgothian Sylex was a mysterious ancient artifact, described as a large bowl made of a copper-like metal with curious glyphs on it, which roughly translate as "Use to wipe the world clean, to topple the empires, to start again".
The Sylex was discovered by Feldon in the Ronom glacier during the Brothers' War. When Terisia City was besieged by Mishra's forces, Feldon entrusted the relic to Loran. Ashnod captured Loran, and passed the Sylex through Tawnos to Urza, on Argoth, where Urza activated the device. The ensuing Sylex Blast destroyed both Urza's and Mishra's armies, altered Dominaria's climate to begin the Ice Age, and caused the downfall of most of Dominaria's major civilizations. So terrible was the blast that Dominaria began to form the Shard of the Twelve Worlds, which trapped twelve planes in a bubble from the rest of the multiverse and stopped any transplanar magic or technology from reaching them. While this kept Urza out, it also helped protect the devastated Dominaria from Phyrexia, preventing them from entering for almost 3,000 years, when the Shard finally fell.
Long after the Brothers' War, the planeswalker Ravidel obtained the Golgothian Sylex through a bargain after a duel with Ash Warlord Embereck in a sunken city of Terisiare after the Ice Age. In Year One by the Reckoning of the Sages of Minorad, Ravidel appeared at Minorad and threatened to use the Sylex unless the five planeswalkers present—Liana of Minorad, Ash Warlord Embereck, Kristina of the Woods, Grenfell Mor of Golthonor and Altair of Coloni – promised not to interfere with his actions on Dominaria, to which they agreed. In the year 1281 by the Reckoning of the Sages of Minorad, Ravidel threatened to use it again, so Jared Carthalion and Kristina found the long-daggers that would destroy the Sylex. Jared used the daggers to make the Sylex vulnerable to a shatter spell, which finally destroyed the artifact.
Powers and Stats
Tier: At least 6-A
Name: Golgothian Sylex
Origin: Magic: The Gathering
Age: Unknown, already ancient by the time of the Brothers' War.
Classification: Ancient artifact, Superweapon
Wielders: Urza, Ravidel
Powers and Abilities: Can destroy continents and cause severe weather changes on a global scale while the energy released from it caused time rifts across Dominaria and formed the Shard of the Twelve Worlds, a multi-universal bubble enveloping Dominaria and eleven other planes.
Attack Potency: At least Continent level (Destroyed the island of Argoth along with its tectonic plate and threw Dominaria into a 2500-year long ice age). The Sylex Blast was of such magnitude that it caused time rifts and created a multi-universal bubble trapping Dominaria and eleven other planes within, effectively cutting them off from the rest of the Multiverse.
Durability: At least Continent level (Survived its own devastating power), likely much higher
Range: Continental; Multi-Universal with the Shard of the Twelve Worlds.
Weaknesses: None notable, though it became vulnerable to a shatter spell once the long-daggers were used on it.