Gabwelius, a enigmatic cosmic being from Planet Cray, resembles a plush creature masking immense power. After Sybilt, a malevolent force, psychically annihilated Gabwelius' tribe, the entity became the lone survivor and pursued its foe to Earth. To combat Sybilt’s corruption, Gabwelius forged the "Fated One" cards, launching the "Fated Clash"—a tournament pitting six warriors against one another, their battles covertly harvesting energy to challenge Sybilt’s dominion.

Years earlier, Gabwelius witnessed Sybilt’s manipulation of Akina Myodo and his sister Hikari, including Sybilt’s decade-long possession of Hikari to siphon her vitality. This compelled Gabwelius to recruit Akina into the tournament, leveraging his resolve to disrupt Sybilt’s schemes. While posing as an impartial arbiter, Gabwelius concealed its agenda, its true allegiance shrouded in mystery.

In Season 2, Sybilt retaliated with "Destined One" cards and the "Destined Showdown," hijacking fighters like Nao Inabe to amass power. Gabwelius allied with Jinki Mukae and Masanori Iseki to dismantle these schemes, culminating in a direct confrontation where Gabwelius confronted Sybilt through Nao. Their final clash descended into a metaphysical duel, with Gabwelius challenging Sybilt’s nihilistic worldview by affirming both selfish and selfless desires as catalysts for change. This confrontation ended with Gabwelius permanently sealing Sybilt, concluding their eons-long rivalry.

Gabwelius’ methods balanced calculated manipulation with deference to human autonomy, its plush exterior belying a strategist entangled in cosmic warfare. Though initially viewing Akina as a tool, Gabwelius grew to respect his selfless tenacity, reflecting the entity’s acknowledgment of desires transcending mere survival. Its duality—a childlike visage juxtaposed with grave, universe-shaping duties—embodied the coexistence of innocence and primordial authority.