Although the twins could not be compared to official guards, they were not to be underestimated.
The twins had also fought together a lot, even back in Terran. Looks and gestures were enough for them to communicate.
The two of them sent barrages of attack to the enemy. From afar, it'd seem like they were careless and just desperate to attack, but the person on the other end of the attacks could say otherwise.
Luke's attacks were all clean and heavy. Although it lacked accuracy, it'd cause damage if not handled well. In contrast, Leo's hits were fast and sharp, hitting the enemy's weaknesses that inevitably revealed themselves as the enemy defended against his brother.
Furthermore, Leo was very smart, and he could control a few water spikes around him while he attacked with his weapon. He was hitting several spots at the same time, slowly chipping away at the man and his equipment's durability.