The Summoning Circle worked with the nature. It was something that took the summoned beasts back to their worlds after the summoner died or when the summoner decided to send them back. It was a natural process.
Since Lucifer tried to use his decay on the Summoning Circles, something changed in the circles. It was as if his decay did damage the Summoning Circle but not the way he was expecting.
Instead of stopping the Summoning Circle, he damaged the limiter of the Circle, which made sure that only Summoned Beasts were called back.
The summoning circle spread to find five meters, swallowing everything inside, living and dead. All the bodies disappeared. Salazar also disappeared, and so did Jenilia.
The entire place was left empty.
After half an hour, Milena reached the place with her team.
"Looking at the scene, it should be the place where the battle took place. Apparently it's already over," Arthur commented, observing the scene.