Powers and Abilities Edit
It has been called the "cursed branch" and the "cursed bough" due to having an extremely powerful mutagenic effect on pierced targets. This causes rapid disintegration (even for non-biological objects like ships), wounds that do not heal easily and contamination of surrounding land. It's similar to the corruption that happens around Queen Nests and fallen Blue Flower debris. The defensive barrier that AB Sword Number 680 creates can greatly reduce the mutagenic effect of Mysteltein.
Not only can it be thrown at extremely high velocity, but Hyperion demonstrates that its direction can be controlled while in flight, leading to utter devastation of multiple targets very rapidly. After the defeat of Hyperion it was recovered and studied in order to use its power for the spears wielded by the Raven Units. When Hyperion Repair later appears he summons Mysteltein from a great distance, totally destroying its field vault for the Raven spears as it instantly responds to his will.
Speaking about Zion being subdued by these spears, "There's no point. That's our ace in the hole to substitute the AB Element. She won't be able to resist. Those spears are just replicas... ...that only resonate the original. And the curse that enables the resonance comes from... Mysteltein. The cursed piece of wood from the enemy." Robert Nelson, (AE2 - Ch30)
"It was a terrible curse... 30 years have passed, but no one can inhabit on the earth that was struck with that bough." Tinie, (AE2 - Ch17)"That thing's holding... The nightmare of planet Arle." Random solider, speaking about Hyperion. (AE2 - Ch56)