@xinneth Hyoo-ri didn't train Hak. Mundok did.
Seriously, Hyoo-ri is the greatest Arse Pull of this series and this author. His introduction throws out of the window all her hard work playing Hak up as invincible, able to stand shoulder to shoulder with the Four Dragons, even allowing for speculation that he might be the Shield or the Sword of the prophecy. You don't just change a character from "overpowered" to "only alive because of plot armour" in the course of a series without being called slipshod in your handwriting. Kusanagi did it in the course of
one chapter and we're supposed to swallow that?
Why wasn't Hyoo-ri following Soo-won around in Awa and the Water Tribe? Heck, why wasn't Hyoo-ri tailing Yu-hon instead of Kei-shuk?
Rubbish, I say. Even if Hak defeats Hyoo-ri later (How so, because his having a sword instead of his glaive was a handicap? Give me a break!), the damage is done. He completely lost to Soo-won's bodyguard, which means he never was a threat to Soo-won in the first place. So all the tension on that front was a sham.
What a stupid move, Kusanagi. The only thing that could bring this series any lower would be if the senjuusou were actually able to cure Soo-won.