Stephen waited until Loki and Theo were well out of the way, taking the time to catch his breath and prepare himself for the final spell. He recalled how the Conductor had stressed how important it was that they leave no evidence behind and the spell he had decided to use to accomplish that take. Once he was sure they were safely beyond bounds. he raised his hands and cast the Icy Tendrils of Ikthalon.
Purplish-white eldritch energy erupted from the ground in think tendrils, wrapping around every piece of robot shrapnel and the vehicles the robots had arrived in. Once everything they had to get rid of was secured by the magic, the tendrils yanked their cargo down deep into the earth. Stephen focused all his energy and getting them down as far as possible, several miles beneath the highway. The eldritch energy vanished. The ground was left just as it was before the trucks arrived with no traces left behind of the carnage the three of them had caused.
"Think that will do?" he called out to Theo and Loki, his lopsided grin in contrast to how utterly exhausted he felt.