Kazuma's and Ryuhou's evolving Alters and fighting styles:
It is interesting to note that Kazuma's and Ryuhou's Alters are symbolic interpretations of their character development. For instance, Kazuma's initial Alter is an amalgamation of his brewing anger, but his Alter eventually becomes more and more aggressively aesthetic as he grows more and more angered throughout the series. Also, his "Harmonic Alter" is symbolic of his close relationships with the people around him. In contrast, Ryuhou's separate Alter is representative of his separation from the people he loves, and as he develops closer to people as his character develops, he eventually becomes one with his Alter.
The polarity between the two are also represented through their Alters. Kazuma is completely harmonized with his Alter, whereas Ryuhou, even when he has become one with his Alter, merely uses it as an armor rather than part of his actual, physical being. Their Alters also reflect their personalities. Also, Kazuma's Alter is bright, red, fiery and representative of sheer force: His final Alter even looks as though he's a lion of sorts or a red oni (Japanese Ogre). On the other hand, Ryuhou's Alter is consisted of cool colors with sleek edges and precisely-damaging weapons, which in return make him look like a knight or a blue oni (Japanese Ogre).
Their Alter powers are also reminscent of their differing fighting styles. Kazuma, who tends to use sheer force rather than subtlety, has an Alter which delivers massive power rather than precision. Ryuhou's Alter uses precise, hitting tactics to fight. Kazuma likes to use his fists, thus his Alter increases the strength of his fists. Ryuhou's fighting style implements a type of martial art where he uses his open palms in precise, cutting actions, so his initial Alter uses attacks that use precise, cutting actions, and when he finally integrates with his Alter, he can create a shield/blade that augments his open palm technique.
All of these factors combine in their final duel in episode 26, which is best described as a demonstration of the ancient question, "What would happen if an unstoppable force (Kazuma) came into conflict with an immovable object (Ryuho)?".
The ever-ongoing rivalry between these two characters can also be seen as symobolic of the struggle between chaos (Kazuma) and order (Ryuho).