Derek naturally had a way.
Even if the amount of moon thralls in this area was so dense that it'd be inconvenient to sneak in even with Nihility, Derek still had many other methods.
He could use Nihility to create clones and lure the monsters away, then kill the moon thralls little by little. He could also use Nihility to forcibly break through, then switch places with his true body... But he chose the simplest method.
Rush in flying.
That's right, moon thralls had a very embarrassing shortcoming—that is, because their overall strength was weak, even today, moon thralls with flight abilities had still yet to appear.
Heroic Spirit summoners in the Morningstar Plane didn't temper their own bodies too much, so very few people had the ability to fly. This was true even among Tier 3 experts.
