William had a monstrous weapon, one that could control the earth's elements perfectly fine. Yet he still needed all of them to make the scary grand technique.
"Screw it! Taking one out won't greatly weaken my technique. And I'm already close to my limit, so it won't differ if I stopped now…"
He decided to take the risk after five more minutes, ending up taking the monstrous weapon with earth element out from the formation. The moment he did that, the entire grand technique faltered, and started to show signs of instability, and its effect wasn't that great in the end.
He didn't care about that. He left his earth-based monstrous weapon to handle the restructure of the entire terrain around him while he kept defending the zone he selected as his rest spot with other monstrous weapons.
Even if his grand technique suffered a weakness, it was still scary. The petrification effect continued, but lasted for much less time, and covered a much smaller area.
