The Coalition War Arc, by premise and execution, simply put remains the most exhilarating chapter in all of Kingdom to this day, and that is saying something considering what an action-packed manga it is. This is the arc in which Hara, in my view, really began setting himself apart from the pack as a master of crafting and weaving tension, drama and stakes with such coherence and brevity. In my estimation it is this style that makes Kingdom the most consistently rewarding, exciting and intriguing manga out there, in my opinion surpassing even One Piece. The Coalition War Arc is deliriously exciting, dramatic and an utter joy to read.
My second favourite arc is the Western Zhao Invasion Arc. I love it, but I do have gripes with it. This arc provided a lot of pay off with respect to debuting the mysterious Ou Sen's power and that of his army, the perspective of a grand invasion force, the ascension of the young Qin talents - and so much more. There was a lot of pay off with Shin in particular in this arc, and that's always a big plus for me, but I also enjoyed witnessing Mou Ten shine in his post as a field-promoted general; Ou Hon's reversal that resulted in the Ba Nan Ji Army being effectively destroyed and in need of regrouping for the following days, as well as his duels with Gyou'un; Yo Tan Wa finessing victory from out of the jaws of defeat; the cloak and danger plot in Gyou; this arc was just nuts in how well it resolved so many of its plot threads almost as seamlessly as they were woven into the story. As for my gripes, I'll save those for another post for another day, but all in all WZI is my #2 arc.
Third is a bit of a doozy because a) Bayou is great, b) Sanyou is great, and c) the Zhao Retaliation Arc is quickly approaching over the horizon and quite possibly may end up taking the #1 spot.
Bayou gave us a true taste of warfare and battle between those at the top. It was the battle at which the Hi Shin Unit was born. The beginning of Shin's enmity with RBK. The beginning of his dream in earnest. It was at Bayou that Shin learned his first lesson of what it would take to become a Great General of the Heavens as he and Hyou dreamt of since they were young boys. It was at Bayou that Shin first tasted the pain and sacrifice that waited him, and he proceeded along the path with conviction. Bayou had tension, drama and heaps of critical character development that would continue to pay off for the following hundreds of chapters.
Sanyou was the first step on Shin's path to becoming a Great General that he approached and understood with clarity. The introduction of Ou Hon and Mou Ten were very memorable and had seismic impact. Rin Ko was a great foil and quite a perfect crucible/wall for Shin to overcome. All of the Four Heavenly Kings were interesting, but it was of course Ren Pa that was the star of the show. He was like a meeting of the earnest love of warfare that we saw in Duke Hyou and the heroic, ambitious and selfish mannerisms of the 6GG and 3GH. Sanyou had wit, suspense and just a great collection of action scenes. I do miss the crafty Shin we saw competing with Ou Hon back then.
It feels unfair to pick ZR because we're only 20 chapters in (though that also speaks to the quality of the writing thus far), but I am certainly loving it and if I were to give it my #3 spot for now, I'd be having my cake and eating it to, too, in a way, because the ZR is basically a repeat of Bayou, only this time the Qin fell into RBK's trap while they were on the offensive, and Shin isn't some wet-behind-the-ears whelp, but a seasoned and accomplished veteran and general in command of a powerful army. As it stands, I think ZRA will comfortably take the #3 spot eventually, and quite possibly surpass Gyou.