The moment these parts would reach the target, they'd start attacking it for a few seconds, then exploding fiercely to add more damage to the target.
What William did just now was to simply dash forward, using his lightning element, stopping the incoming parts of that monster.
Then everything rolled the same way he expected!
These parts were going to attack any nearby target, and that made William continue his move and not stop, returning back to the same spot he moved from.
Standing almost fifty metres away made him sure he'd not get hit by these parts or get touched by the explosions they'd release. But it was a totally different story for the monsters around.
William made sure to leave the area around them densely packed with monsters. So, the moment he stopped this crazy flashing movement of the monster parts and retreated, they released their aura and special substance in the air, before these parts started to madly attack the monsters around.