Ghirahim was the anti-Zant for me. Zant built my expectations for the final battle, and I thought he was among one of the most intriguing bosses that I had ever encountered. It was not until I was finally toe-to-toe with the Twili usurper did I realize that he was an emotional unstable puppet whose temper tantrum ruined every image I ever had of him. Zant made me think that he was the main antagonist - that his fall would save Hyrule - but he was simply a puppet for Ganondorf.
Ghirahim, however, did a trick that I do in geometry; I lower my teacher's expectations when practicing designs, and then annihilate the final design. I had little expectation for Ghirahim; he seemed overemotional from the start. In addition to his weird tongue, I couldn't take Ghirahim the least bit seriously. His "Sick with anger" bit only shot my feelings towards him closer to dislike than indifference.
It was not until he revealed his true form that I began to actually respect him. Finally, he became an adversary worthy of taking seriously. Among one of the most interesting things is the fact that he feels exactly the same way about Link. You see, as the game progresses, that Ghirahim begins to actually take Link seriously. Ghirahim stops toying with Link, and actually begins fighting back in the later phases.
I had always known that Ghirahim was Demise's puppet, but I didn't realize that, when pushed over the edge, he would explode quite like he did. It became less about taking Zelda or reviving his Master; Ghirahim made this personal. He decided that Link
had to die. He sent entire hoards of Bokoblins after Link in the hopes of defeating him, before finally showing Link his true form.
This final effort to destroy Link shows a side to Ghirahim that I didn't know existed. I always saw Ghirahim as a more feminine enemy, which gave me the incentive to create the thread,
"Does Ghirahim Intimidate You?" prior to the game's release. Many people said that they were intimidated by him on an emotional level, but not on a physical one. Ghirahim, in his final form, showed a side that could easily intimidate one on both levels - physical and emotional.
I think that Azure Sage's comment in the linked thread fits Ghirahim in his final form quite well;
Azure Sage said:
Ghirahim is a genuine example of the saying, "Don't judge a book by it's cover."
I didn't expect Ghirahim to evolve this way. I never stopped and thought that he was hiding anything from us. I felt quite the opposite; I felt that he showed us too much when he had his meltdowns, but now we see that there were tricks still up his sleeve. As the original poster mentioned, Ghirahim gets scaly gauntlets in your second battle with him. Perhaps this was a form of foreshadowing for his final form? If it was, I most certainly did not catch it.
The evolution of Ghirahim is interesting because most of it is entirely internal. He never took Link seriously, until he realized that he may actually get in the way of this Demon Lord's efforts to revive Demise. When the final standoff came, Ghirahim revealed his final trick up his sleeve; his final form. It's interesting just how Ghirahim evolves. Unlike Zant, it was a good evolution, rather than being detrimental to his character development. I disliked a lot of
Skyward Sword, but Ghirahim was one of the positive things about the game.