Blue eyed devil
As hectic and dangerous as the fights were in the fog, it also worked to Nero's benefit. Everyone was fighting randomly, and though the fights were not too intense, that was mostly because being unable to tell what was happening around them made everyone nervous.
So naturally, in the middle of fights, when everyone's nerves were tense, the sight of Nero and Harold emerging from the white haze startled and distracted them.
But they did not remain nervous for long, as the only thing that surpassed their individual strengths was their impeccable teamwork. Although Nero had not specifically trained with anyone other than Jackal since he got his ability, sometimes training wasn't needed.
Although Nero didn't know the exact details of Harold's ability, he knew it was similar to a tremor. It could pass through armour and shield, and if used correctly could even cause the opponent to drop their weapon due to the heavy vibrations.