I never mind friending TFS people, I just tend to do it as I interact with them regularly/if we end up threading and I want to discuss the thread or CR with them
Ken is in the same boat as Chikusa in that he was experimented on as a child, and in his case it's much more obvious what was done to him because you actually see the effects in canon
Specifically, Ken - who is rather dumb and animalistic even in his base state - is able to 'channel' certain animals through the use of fang cartridges (which just look like fake Halloween teeth of various configurations, tbh) that he puts on over his own teeth.
It's never explained what was done to him to accomplish this, but the manga shows a rather horrifying picture of a tiny Ken strapped into a chair with a ton of tubes attached to the inside of his mouth, screaming
I personally state it as them having actually spliced various kinds of animal DNA into Ken, which Ken's flames are actually able to activate and incorporate into how Ken's body works
Ken, for his part, has Sun flames! Their property is Activation - generally, Sun flames work by enhancing a body's physical abilities, such as strengthening muscles beyond ordinary human limits or accelerating natural healing processes. (They can even accelerate hair and nail growth, though that usually doesn't have much practical application.)
This ties very neatly into the fact that when Ken slots in a cartridge over his teeth, they trigger a specific reaction in his body where his muscles, senses, teeth, and nails tend to grow to give him the appreciable abilities of a specific animal.
(Somehow, in the process, his cartridge apparently fuses to his own teeth until he takes it out by choice. KHR says don't ask questions about this because it doesn't have answers for you.)
It's pretty obvious that how Ken's channels work is directly caused by his Sun flames in some way, since they focus specifically on enhancing his body's physical abilities in a way that aligns perfectly with how Sun flames work.
Presumably the experiments just sort of...established certain physical configurations, tied to his cartridges, that mean Ken doesn't even have to understand his flames or know how to consciously use them in order to trigger their use; he just has to use the cartridges and the cartridge delivers instructions to his body in regards to how to change.
Waver's got a student a bit like him (that he raised since nine pretty much along with one other) that uses Beast magecraft so hmmm... this will feel a little familiar to him
Here's how I'd write it right now. Discerning Eye would pick up the flames being activated by any cartridge, and see how the flames effect the changes by enhancing him and pick up the changes are pre-programmed. Could Waver guess at each channel's abilities? Yes... but he couldn't measure their exact output.
Stat reading is a Master skill, and reserved for measuring Servants only. ... though Waver's the only Servant in TFS capable of acting as such, he isn't contracted the right way to give him access to that
> ken: /kong channel
> chikusa: don't like that
that's a liealthough the only other dog he has to deal with is bon the hat eater, so the competition isn't that vast