Cosmog was repairing the space Nihilego had forced open!
He did indeed have that ability, the so-called deity power of a legendary Pokémon.
But Nihilego would not meekly stop. Whenever Cosmog pushed some of it back in, Nihilego pushed back out, making Cosmog very inefficient at filling the gaps in spacetime.
"How can we help him?"
If Ribombee had been full of energy, she might have been able to approach the area dense with Ultra Infinity Energy and interfere with Nihilego.
But now...
"Mee!"
Ribombee reached behind Lillie's waist and took out a Poké Ball.
"Chirr~"
Metal scraped and meshed with a sound. The intricate, magnificent mechanical girl turned the gears in her joints and curiously surveyed her surroundings.
The Ultra Infinity Energy did not seem to affect him in the slightest.
"Magearna!"
An artificial Mythical Pokémon, she had been created by the finest craftsman in the Azoth Kingdom five hundred years ago and presented to the king's daughter.
Lillie had indeed received a Magearna from her father.
Mythical Pokémon fell within the broader category of legendary Pokémon, but Magearna had not formed naturally and possessed no profound power to maintain the laws and order of the world, unlike Celebi and Jirachi.
Still, thanks to her special nature as a Mythical Pokémon, Magearna was completely unaffected by Ultra Infinity Energy.
"Chirr?"
"Mee!"
"Chirr!"
In a few brief exchanges, Ribombee told Magearna what had happened to Lillie.
While at Aether Paradise, Lillie had been beguiled by Nihilego into coming to Poni Canyon.
By the time Ribombee emerged, she already had to devote herself entirely to resisting the Ultra Infinity Energy.
If she had had more room to maneuver, if she had noticed sooner and called Magearna out in advance, Lillie at least would not have come so close to the brink