Rudra wasn't a genius and amazingly smart like Thor.
He wasn't as skilled or as graceful in combat as Iris.
But Rudra has had the most growth out of the three of them by far for one simple reason.
He was a mentality monster!
And he was practical in how he trained instead of emotional like the other two were.
Thor trained into his strength and adapted to his blindness, while Iris trained to become better at her field as a swordswoman.
Rudra didn't have one aspect of combat that he excelled in, he wasn't as singularly talented as Iris and Thor.
But he was a monster when it came to the act of combat itself!
After the battle of Agni Igris and Kong, he was inspired by the way he dominated his opponent. And he wanted that power for himself!
'How does one attain such mastery?' Rudra pondered, his fists clenching at his sides. 'My strength alone is insufficient. I must transcend my current limits.'
