One had to wonder how a Bijuu cloak stopped something like Athos' Chidori Nagashi from doing any type of damage at all, or how Kamui's blade struck his skin and somehow Kamui managed to get back into the air(?), and cast two giant Rasengans all before Athos' would hit him..? Well, whatever type of witchcraft seemed to be at work here, it didn't really matter in the slightest. Despite Kamui's claims of enhanced sense, following Athos by now would be a monumental task. The waves of snow already started to cover the ground in inches of thick and heavy snow, and being made of Athos' chakra, it stopped any type of sensing from being able to tell where Athos would actually be. If Kamui were standing right now, instead of attacking Athos, even in their proximity the man would not be able to see the hulking red head, just to give an example of the intensity of the blizzard. Athos, of course, could see what was happening perfectly because of his Mind's Eye, which really made the clone's dropping of the smoke bomb pointless but that wasn't something Kamui would've been able to tell. They also wouldn't be able to see the snow and how it'd swallow the marked kunai that Kamui stuck into the ground.
Even though Kamui used Hiraishin, Athos could tell that the man was, to put it simply, still understanding how this art was used. The battlefield was Athos' and Kamui hadn't noticed or made a single attempt to stop it from happening. For starters, the snow that was made of his chakra now coated, not only, Kamui but Kamui's clone, which meant that Athos' chakra was just as stuck to them as the snow was currently. Athos could've stood still and taken the blow of Kamui's dual-giant-Rasengan and have walked away with nothing but, well, nothing. But he didn't plan on letting that happen. With Kamui's dual attack coming towards him, even if Kamui was able to see in front of him normally, with two large attacks such as this one, it would've made it impossible for Kamui to see Athos around the large forming balls of blue. But now, even as Kamui had called himself, Athos knew the man was a sitting duck and he used that to his advantage.
Athos would be gone within a single second from where he stood, and if the snow wasn't blinding and Kamui's vision wasn't blocked by his own attack, there would've been a flash to see but sadly for the man, this would go unnoticed and Kamui would have no way of knowing that Athos was even gone from in front of him. When Athos reappeared, he would behind the Nine Tails Jinchuuriki, having used the chakra that was all over Kamui to use him as a place to teleport. Athos was fast, this was stated before and with Kamui in the middle of his attack and believing Athos was still there, the man had the upper hand. His right hand moved, in a blur that would move from where Athos was and to it's point of connection within the span of less than a half second, actually, perhaps it was even faster than that. Given Athos' long standing mastery over the Lightning Element, it was easy as breathing to place a Jutsu upon the hand that moved to strike Kamui but the move that came forth was just as instant as the rest of Athos' movements had been. With only his index finger pointed outwards, a One Finger Nukite Hellstab aimed to tear through the chest of Kamui, Athos' arm big enough not to pierce the heart but to completely erase it from existence as it'd be pierced.
From the sudden Hiraishin, to an attack that would only take fractions of a second, and the blinding circumstances of the fight, Athos aimed to have ended Kamui's life before Kamui would even be finished his Rasengan attack, or before he'd even be able to tell that Athos was no longer behind Kamui. Perhaps this wasn't a type of fair tactic, or something of the sort, but threats are to be put down as fast as possible... And that is what Athos was aiming to do.