I'm not readin everything as I've lots to do atm, but here's my 2 cents on the killua strength part.
He is not as strong as any the fighting members of the spiders, heck not even Machi. He is not as strong as even Knuckle. Lastly Gon did not surpass Uvon.
Nen attack and defense works like this
- Maximum Aura Power or M.A.P. (最大オーラ量 or MOP): the amount of aura stored inside the body of a Nen user. It varies for each individual and can be increased through training.
- Potential Aura Power or P.A.P. (潜在オーラ量 or POP): the amount of aura that a Nen user can expend before passing out.\
- Actual Aura Power or A.A.P. (顕在オーラ量 or AOP): the quantity of aura that is used effectively at any moment. This is what determines the efficiency of the Nen user in a combat situation, as a high P.A.P. with a low A.A.P. is meaningless. A.A.P. can be increased through training. It is also influenced by how well an individual can use Nen: lack of practice or low affinity for a certain Nen category can cause it to be lower than the aura units actually expended. For example, when Gon used his Round 2 technique against Knuckle, he consumed 4000 aura to charge two abilities, Rock and Paper; however, the actual force of the Emission attack was equivalent only to 500 aura, 25% of the power of Rock and 12.5% of the aura consumed overall.[31]
- Ko (硬, Temper) is an enhanced version of Gyo in which all of an individual's aura is concentrated into one particular body part. It is a combination of Ten, Zetsu, Ren and Gyo. Zetsu is used to completely stop the flow of Nen in all other parts of the body. This makes that one body part exceptionally powerful, but leaves the rest of the body completely unprotected. This is used by some Nen-users as an offensive technique (a Ko-punch would carry all 100% of your aura with it), but it is a risky move — leaving the rest of one's body unprotected in a fight against another Nen-user is generally not a good idea. Ko results in one's aura creating a high-pitched dissonance, somewhat akin to the sound of metal being ground.
- Ryu (流, Flow) is the term for real-time use of Gyo (the adjustment of aura concentration in various body parts) by a Nen-user in battle. For example, the use of Gyo to increase the amount of Nen in a fist as one strikes with it, to increase damage done; or to increase the amount of Nen in an arm as it is used to block a blow, for extra defense.
Gon's Rock is him charging up his
KO representing his PAP, just like Uvon's BBI. Question: Who has the faster charge rate? Who has the more destructive force?
Gon's AAP, his normal nen enhanced punch is nowhere near Uvogin's but is actually higher than Killua's because he is an enhancer therefore 100% enhancement. Killua's Kanmaru greatly deminishes his punching power because he spreads his aura unto his body and focuses mostly on the feet.
Evidence:
Gon was toyed by knuckle in their practice, showing that Gon's knowledge of
Ryu is weak at best, and that knuckle can more than enough withstand his normal punches Enhancer to enhancer. What can killua do to knuckle? punch per punch a transmuter can never take an edge over an enhancer unless he's that overwhelmingly strong which killua isn't compared to knuckle. Knuckle as you see is nowhere near Uvogin's power level, although an experienced pro hunter, a very smart fighter, but is an ant compared to Uvogin in pure power. Heck even Morel who has a very large M.O.P would rather not fight directly with a pure powerhouse like Uvogin.
Conclusion:
So in terms of Kanmaru killing somebody he'd have to do it stealthily to succeed. If it were a straight up confrontation within a 10 meter distance, Nobunaga(an enhancer), has the M.O.P, and A.A.P to generate enough defensive aura to block a critical hit from Killua(transmuter)whose punching/slicing/stabbing power is diminished significantly due to kanmaru usage.
