Chimera Ant Arc
(Some spoilers, especially the videos displayed!)
I've never been so stressed out and emotionally drained from an Anime as much as the Chimera Ant Arc threw at me. From Killua and Gon's friendship, to new enemies arising with the mutant Ants running about killing everything in their path, to Gon trying to find his father but found one of his best students, to all the crazy battles, alliances, and betrayals.
This arc had me pissed off and wanting the King, the main super powered bad guy, to be beheaded and burned for the atrocities he caused, not to mention all the underlings, the soldiers, and squad leaders of various mutations who murdered and kidnapped humans, especially children so the Queen could eat and feed her baby inside her womb, which would turn out to be the coldhearted King, who wanted to take over the world because it was his right to do so. Bastard.
I probably don't make much sense at the moment since today was the day we finished this arc of the series and it might be the best of Hunter X Hunter. It left me wishing there was more. I was emotionally attached to all involved, including random characters that were just there for opposition, including Cheetu, who was a humanoid Cheetah looking Ant, who was lightning quick, and constantly needed attention. Colt, various parts of bug and animal I guess, plus the first that had human genes, which basically changed the whole litter of Ants that came after him. Ikalgo , Welfin, and Meleoron are several others that didn't seem important when you first meet them but turns out those characters are pretty good.
This arc also shows the Hunters Associations chairman's power, as Isaac Netero, one of the most powerful in the world despite his age heads to deal with the threat of the Ants with a few others, its shows that Netero is in a class of his own, almost like a Mr. Miyagi/Master Roshi (karate kid, Dragon Ball Z) type character, who put the Hunters Association above all else. He disposed of most the Ants forces easily, but his main mission was to take out the King, who seemed all but impossible to beat.
Gon and Killua continued to power up during this arc, but suffered some big time losses. This entire series was showing Killua being in the darkness and Gon being the light, this arc slowly brought Gon into the dark and brought Killua into the light with some amazing storytelling. Gon also seems insane at times, like a pure nut job.
The Phantom Troupe make an appearance back to their home which was a fun moment since they were deemed the bad guys, it shows that they love their home and would fight to protect it against the invading Ant mutants that tried to take it over. They go in and like a bunch of kids make it almost like a competition to see who takes the head Ant there first. All of them had their moments to shine and they showed how dangerous they still are.
The fights were a lot better in this arc than the last few as well, I guess because it was about surviving and destroying one race or the other. It was a war. A war that only those strong enough, like the Hunters and Assassins of the world could fight. The battle between Gon and Pitou was sick as hell! It gave you a horror type feeling from a character that his been slowly losing it, a kid, who should have no business fighting someone with the power level as Pitou, turned into something Pitou was frightened of, that was absolutely awesome!