No matter what, based on what he has said, it's definitely not wrong to take him down first. William thought as he looked at the other party's serious expression.
If it was as he had guessed, the other party was from another timeline. The other party must have been facing Remides and the others before saying that 'we have to kill this Judge.'
This was definitely enough reason for him to attack.
William made his move.
Frost spell, Declaration.
Due to the influence of the Ironstone Oath, William couldn't cast Divine Realm spells that consumed massive amounts of mana unless he used the Holy Spirit Disc. However, the Holy Spirit Disc in his hand was destined to be used in the battle with the Lady of Starvation. He didn't plan on wasting any valuable resources to deal with the person in front of him.
Therefore, he used Demon Spear that was certain to hit.