Morglay is a gigantic, Anti-Planetary Class Phenomenon Weapon. Notably heralded by Fear, it's the first such weapon to be revealed in the series. Physically it's a dual-ended blade that's up to half a kilometer long in its largest version.
The two versions that have been shown so far are notably different in appearance. Morglay was originally wielded by SS-Class EX-Type Zero "Ingrid" in Cosmic Century 367, 55 Years before the Battle of Velchees. This is the same one that's seen in Bishop's collection.
The other version is seen with the four Morglay of Central Order used by Fear. Dry mentions that these were CO's secret weapon, though it's unknown if they were created through research or if they were appropriated from the Beasts.
Powers and Abilities Edit
Morglay extends a massive barrier, which locks with a physical object and moves it in a certain manner that the user presets. The power of the weapon was demonstrated when it first penetrated the planetary shield emitted by the underground Fortress of Eden on Valtia, then pierced the facility's shield generator itself in the core of the fortress. The goal of this attack was to destroy Eden so that the population would have nowhere to seek shelter, inducing panic in the survivors and halting preparations for the assault on Arin.
The potency of Morglay is further demonstrated when the true target of the weapon was revealed to be the halting of the movements Valtia's mantle to disable the planet's magnetic field and induce climate change.
"One of the Morglay's accelerated!!! It accelerated like a lightning bolt without propulsion!! No way! It's defying the laws of nature..." 
"...What? It is... The feeling that I've experienced... The closed space created by Morglay... I experienced it once in a top secret 4th special lab experiment." Anne, commenting on the massive barrier emitting from the Morglay that had just struck Valtia. 
"Morglay's particular orbit was set in advance and actualized with maximum physical power. Besides, it is a weapon for anti-planet, anti-fortress. It's useless for a fight against human beings." Leo 
"We need a large amount of AB Ore that hasn't been forged into AB Swords. But without Central, we can't get them. At this rate, it will take at least 7 months to remove the closed space and even if it's removed, the outer core's rotation has already stopped... This planet will be... Morglay's closed space that Anne had told me about...It is fixing the space with it's Supernatural Power and shifting the planet's rotation and revolution axis... What the hell is this Supernatural Power? Besides, the sword itself is a kind of wave-type weapon... Stopping a planet's outer core rotation... Supernatural Power or whatever it is, even if we break that power, this planet is done for." Dr. Thor 
"Naricapha was also destroyed by Morglay. Dalita and Puyan... Every single large-scale base has been destroyed... It seems that four Morglay's have been used in the worst way." 
- ↑ 1.0 1.1 1.2 http://www.webtoons.com/en/fantasy/knight-run/ep-20-pray-part-18/viewer?title_no=67&episode_no=21
- ↑ http://www.webtoons.com/en/fantasy/knight-run/ep-23-pray-part-21/viewer?title_no=67&episode_no=24
- ↑ 3.0 3.1 http://www.webtoons.com/en/fantasy/knight-run/ep-24-pray-part-22/viewer?title_no=67&episode_no=25