Rocky was able to stand undefeated in the midst of an onslaught from nine others not just because of his own skill or because of his Armor, but also because he chose aerial combat.
The combat of the Void Magic Armor is distinct from traditional fights. If one doesn't understand how to use the Armor, especially how to take advantage of its aerial combat superiority, then there isn't much difference between a Void Magic Armor and a regular Armor.
The opponents Rocky faced were just like this.
Whether it was the triplet brothers, or Powerful Peter, or the others, none of them were true Void Magic Warriors. Their use of the Armor was still at a basic level, barely able to utilize all of the Armor's functions, let alone leverage its aerial advantages. It was simply beyond them.
That's why, despite their numbers, they were no match for Rocky in the air.
This was also why Rocky stayed in mid-air right from the start—he intended to use his strengths to target their weaknesses!
