Divine Messenger Lydia:
The heroes led by Spezion wanted to escape. But Starlight's Lattice beheld the power of light from the Gods, and it wasn't to be destroyed by the power of heroes. After some time later, a hero and an excellent sorcerer Josephina was successful in creating the magic of death that can destroy Starlight's Lattice by borrowing Shilen's power. That was... the Decaying Darkness.
Spezion and other heroes attempted to use this Decaying Darkness to destroy the Starlight's Lattice and convey their wishes to the gods. But all of them had to risk their life, as it was a great magic powerful enough to destroy the Starlight's Lattice and demanded much.
In the end, Octavis swallowed the Decaying Darkness and died, and the attempt to escape failed. It could have been his faith in god, simple hesitation, or just lack of resolution that caused it, but I have no way of knowing.