The Giga Slave is the most powerful and secretive spell in all
Black Magic in the
Slayers Universe. It was created by
Lina Inverse, and it draws its power from the
Lord of Nightmares, the source of all chaos.
Since Lina seems to be the only person who knows how to cast the spell, I'm not sure how
Syphiel knew about it, but she warned Lina that by casting it she could consume the entire world in a void. The
Claire Bible later gives Lina a glimpse of how it could have happened if she miscast the Giga Slave. Nonetheless, there are some times when Lina has no choice but to risk it all in order to save the world.
"Darkness beyond blackest pitch, deeper than the deepest night! Lord of Darkness, shining like gold upon the Sea of Chaos, I call upon thee, swear myself to thee! Let the fools who stand before us be destroyed by the power you and I possess! GIGA SLAVE!!"
The chant refers to the
Lord of Nightmares, and, unbeknownst to Lina in the beginning, the spell actually invokes the
Lord of Nightmares into the caster's body.
Not a spell for a third-rate wizard. Also, requires the use of amplification amulets such as Xellos's Boost amulets, the Sword of Light, or maybe the Philosopher's Stone. Since the spell takes tremendous strength from the caster, it sometimes drains their hair and skin of all color after the spell has been cast.