One of the parts I've enjoyed about this art in particular are the growths regrading Gon and Meruem in particular.
In Meruem's debut, he's a ruthless and sociopath who initially views all life as being lower than him, including his Royal Guards. Interacting with them and Komugi however, starts to humanize Meruem more. One part of him that stand out to me for example in particular is how he originally thought raw strength would triumph. But as he begins to play more and more Gungi, he begins to realize mental strength is just as important, biting his arm as a sign of apology for using a dirty tactic. One night Mereum even goes as far to discuss with his Royal Guards that he regretted killing a young child because he believed he ruined that child's potential. Meruem begins to gradually develop respect for the humans through rescuing Komugi contrast to originally killing her and during his fight against Netero.
Meruem becomes more honorable during his character development. He still intends on taking over the world but is also willing to spare humans in his gained respect for them. Even at the fight against him and Netero, Meruem still insists they rationalize a conversation instead of fighting because he was against starting a conflict initially. After being rescued from the explosion by his Royal Guards and meeting with Palm to find Komugi, Meruem even humbly states at one point that he wasn't "worthy of his Royal Guard's respect" and even tried kneeling down to Palm in order to ensure no signs of hostility. Komugi played an significant part in Meruem's growth and development throughout the Chimera Ant Arc. Even in the very final episodes, Meruem wanted to be with Komugi for his last few hours, enjoying a few fun rounds of Gungi. I found it to be a tragic and touching end. Meurem was a very well written villain with very good character development as a whole.
Gon on the other hand, oh boy where do I begin. The Chimera Ant arc as a whole ****** him up extremely hard. A huge difference as to his usual happy, positive to go self to the **** this arc turns him into. That even scared me a fair bit. When both Gon and Killua witnessed Kite's arm being clawed off by Pitou, Gon goes into a fury of rage but is stopped by Killua and they retreated. Gon comes back with a calm, relaxed and optimistic head that Kite will be okay but when infiltrating the castle and finding Komugi and Pitou, is when he gets extremely pissed. Pissed off enough to call Pitou out in giving compassion to Komugi when Pitou just ******* clawed off Kite's arm and even considered holding Komugi as a hostage or murdering her off any given chance Pitou wasted any more time. Even Killua had to step in and calm Gon down in waiting for Pitou to heal Komugi. Pitou eventually gives in to Gon's deal and they both go off to find where Kite is. However it was too late and after Pitou telling Gon he had to be killed, came through Gon's ******* transformation. Good god have ******* mercy as Gon beats the living **** out of Pitou, only to be stopped by Killua in the end.
That was one of the most awesome **** **** I witnessed alongside the 1v1 between Netero and Meruem. But pretty also damn scary given the state Gon is in at that point. After all of this, and he's in a hospital, healing from his coma. Man Gon went through a god damn lot in this arc as a whole.