The fact this series has such a huge amount of tender moments is the best argument against those who accuse it of being shallow or one-dimensional. This series is VERY emotional.
When Fudoh absolutely demolishes Raoh and sends the fearsome and tyrannical King of Fists reeling back in terror with the strength given by the love and courage of his (adopted) children.
Raoh:A man whose stupidity knows no limits... Very well! Then give it your all to scare me and force me to cross this line!
Fudoh:You really don't seem to understand anything.
It gets better: Raoh explicitly told Fudou that this was a tune-up fight, a way to overcome the fear that he had felt against Kenshiro, and told his troops to shoot him were he to step over a line behind him... And it's Fudou simply pointing out the children, with stones in their hands, sadness yet resolve in the children's eyes — the very same in Kenshiro's eyes — that frightens Raoh enough to step over the line, his attempted comeback completely backfiring.
The outcome of Kenshiro and Raoh's final battle, in the 2007 film version:
Raoh:Impossible... how did you defeat the Fist of My Soul...
Kenshiro:Your heart is alone, but in my heart I hold the love I feel for Raoh, Toki and Yuria. Even a mighty fist that can shatter Heaven and Earth can never destroy a heart that holds these small but precious feelings.
Before that, the dying Bat, wanting the amnesiac Lin to be with Kenshiro, tries feebly to insult her and pretends not to know her — however, the warmth and kindness in his eyes actually causes her to regain her memories... and her love for him.
Kenshiro and Yuria's wedding at the beginning of Kenshiro Den. When the temple bells ring, and the spirits of Rei, Toki, Raoh, Jyuza, Souther, Shuh, Ryuga and Ryuken can be seen, giving their blessing on the wedding... Tender Tears were shed.
Even though Hokuto Shinken can have one successor, and Kenshiro is not related to him by blood like Raoh is, Toki as a little boy selflessly saved the former as he lies injured in the bottom of a cliff. When asked by his adoptive father and teacher:
Ryuken:"Why do you do this? If he lives you'll have to fight him one day for the right of succession!!."
To which the future doctor answers:
Toki:"It dosen't matter: he's my precious little brother. Come what may, if it is fate, I'll fight him then. My own brother Raoh didn't think about succession rights when he saved me; so until then, I'll protect my little brother like Raoh protected me."
Rin-chan, but a nine-year-old little girl, chose to literally walk through fire than to submit to Raoh's rule, and inspired an entire city of men to stand up and fight against the invincible tyrant's army through sheer bravery alone; this doubles as her Crowning Moment of Awesome.
Kenshiro halts his journey to reunite with Yuria to save Fudoh, who is about to drown in quicksand to save his adoptive children, in spite of the fact the nigh-invincible Raoh is rapidly approaching the Nanto general and the love of his life.
Fudoh:"Why did you come back for us, Kenshiro? You must abandon us for the future of this world!!"
Kenshiro:"I refuse to build my own future upon the blood and tears of others!!"
When a child Yuria completely thaws the heart of a vile villain called Fudou the Ogre by letting him hold a newborn puppy. The man spends the rest of his days caring for orphans as their father.