Wallace realized that having a conversation with them at this point is impossible. Perhaps, he has to show them that he's not joking around and was truly looking for an answer...
He looked at the 12 magicians activating their Mana Artifacts in front of him. Since they do not have enough time to prepare their magic, most of the skills they were about to cast were only Grade 2 Mana Spells which would barely do anything to his current body.
At this point, only Grade 3 Mana Spells can perhaps affect him and deal some true damage.
Nevertheless, he didn't let them finish their skills and activated his Magic Jammer.
"Ugh! Curse you!"
"It's a Magic Jammer!"
"Use your swords!"
As expected, they do not have a Jammer Canceller with them since they are expecting to face the aliens and not their fellow magicians.