The MC's soul, when perceived in its truest essence, is not a human spirit but a sword. This sword is his very being. He cannot discard it, and no one else can wield it—it is him. Naturally as his soul is a sword, it has its own ability.
Abilities1. Cut (World Severance)
Effect: Allows the MC to slice open the barrier of reality itself.
Appearance: The cut looks like a shimmering crack or an "ink stroke" in the air, widening into a doorway when stabilized.
Limitation: only use is world travel. No combat relation
2. Anker (World Mark)
Effect: The MC can plant a metaphysical "mark" in a world, binding a thread of his soul to it.
Once a world is Ankered, he can return to it through a Cut at any time, even across an infinite distance.