Koilos

Koilos is a mountainous location deep in the mountains of New Argive, part of the Terisian Isles on the plane of Dominaria. It borders the Western Desert and lies at the connection point of the Sardian Mountains and the Kher Ridges. 
==History==
Koilos played an important part in the story of the Thran, the Brothers' War, and the Phyrexian Invasion of Dominaria. 
===The Thran===
During the time of the Thran Empire, the caves of Koilos were known as the Caves of the Damned and were inhabited by the Untouchables. These people were sick with Phthisis due to too much exposure to powerstones through working in the Mana Rig. 
In these caves the planeswalker Dyfed built a permanent portal between Dominaria and Phyrexia. The planar portal could be closed by placing the two halves of the powerstone used to create it onto a pedestal in the caves. At the end of the Thran Civil War Yawgmoth ushered the last survivors into the portal to populate Phyrexia.
===The Brothers’ War===
At the time of the Brothers' War, a few crumbling buildings and a network of caves containing the last technological remnants of the Thran were all that remained of Halcyon, the beautiful capital of the Thran Empire. Calculating the site's position from previously discovered Thran ruins, Urza, Tocasia, and Mishra found the caves during a subsequent Ornithopter expedition. They found an impressive array of artifacts nearby, all left by the Thran. They entered the tunnels and discovered an unusually large powerstone in the Hall of Tagsin, which held a planar portal to Phyrexia closed. Urza and Mishra each claimed one half as theirs. Urza called his half the Mightstone and Mishra's the Weakstone, due to their effects. However, they unwittingly opened the portal between Dominaria and Phyrexia and were attacked by su-chi, forcing them to flee the ruins. The portal closed down again on its own after a brief time.Jeff Grubb (1998). The Brothers' War. Wizards of the Coast 
About 10 years later, Mishra returned, this time with Ashnod. They found the caves dark and abandoned, but they used a su-chi powerstone to reactivate the portal and stepped through into Phyrexia. There, Mishra charmed three dragon engines and brought them back to Dominaria, but they were discovered by Gix and had to flee, the portal closing behind them again.
Realizing he would need air to go through the portal, Gix started sending dreams to the Brotherhood of Gix in the Monastery of Gix. He showed them visions of Phyrexia, and the machine-worshippers saw perfection. He guided them through the desert to Koilos, and though several died in the crossing, twelve of them arrived at the caves and reactivated the portal. Gix stepped through and read the Gixians' minds, then gave his name to the monks, appearing to shape his identity after their object of worship.
Gix kept using Koilos as his base of operations for the remainder of the war, manipulating both sides in the war for Phyrexia's best interests.
===Urza and Xantcha===
Phyrexia sent spies out to Dominaria and gradually infiltrated the region. Xantcha was a sleeper agent initially meant to go there. Xantcha betrayed Phyrexia and teamed up with Urza against her former homeplane. Xantcha and Ratepe, a young man who resembled Urza's brother Mishra, traveled together to Koilos, where Xantcha found she could read some of the Thran glyphs. She realized the Thran and the Phyrexians had common origins, and that Gix had been one of them. Xantcha and Ratepe returned to Urza with the news. Together, the threee returned to the caves to fight Gix. The fight lasted a long time and it seemed like Gix would win, but in the end, Xantcha and Ratepe sacrificed themselves so that Urza could defeat Gix. The Sacrifice at Koilos would directly influence the actions of Urza, leading to the Founding of the Tolarian Academy 30 years later.Lynn Abbey (1998) - Planeswalker, Wizards of the Coast
===The Phyrexian Invasion of Dominaria===
After the Thaw, the site became accessible again. Once more the portal opened and Yawgmoth came through to invade Dominaria, but the Weatherlight sealed it again. While the Phyrexians had the capability by this time to build portals that could be rolled up and operated from any location, the permanent portal in Koilos was still an important site for the Phyrexians to launch attacks from. This made the caves an important battleground throughout the Phyrexian Invasion.
===Second Invasion===
Currently, Koilos is located in New Argive. Due to the unique properties of the Caves of Koilos, not even the most entrepreneurial archeologists or enthusiastic researchers have plundered them. Karn sought the place to find information about the use of the Golgothian Sylex, and found a clay tablet referring to the Sylex.
The Caves turned out to also be the staging ground of the second invasion of the Phyrexians, led by Rona and Sheoldred. Rona was confronted by Karn who managed to bury him under tons of rock. The ancient interplanar and Phyrexian technology in the caves caused low-grade interference and distortion, preventing Karn from planeswalking away. He was eventually found and freed by Ajani Goldmane.
==Trivia==
*In the prerevisionist source, it was Urza who named the place "koilos", the High Argivian word for "secret".Antiquities War, Volume 1. This was later repeated by Xantcha to Ratepe.Abbey, L. (1998) Planeswalker In contrast, the flavor text of implies that the place was already named Koilos in the time of the Thran.
*The name itself is likely borrowed from or inspired by Ancient Greek κοῖλος (koilos), meaning 'hollow' or 'concave'Wiktionary.
==Gallery==
Vault of Whispers BRC.jpg|The prison of Koilos
Hall of Tagsin.jpg|The hall of Tagsin during the Brothers' War
koilos.jpg|The entrance to the caves
Koilos portal.jpg|The portal to Phyrexia
1e Terisiare.jpg|Present-day Koilos is located deep in the mountains
==In-game references==
==Notes and references==
Category:Terisiaran locations