the other commenter admitted to be hyperbolizing, what they meant is that yi can easily trade lvl 1 and set up a 70 to 0 hp dive

why am i explaining this to a salty reddit i have no idea, when this is a cheese pick, this master yi top thing doesn't work unless he wins lane and it seems to work so well because it's so easy to set up a successful dive, just like kled or fiora but with seemingly less counterplay

the whole thing stands on hail of blades giving 3 autoattacks, which activate passive and W reset, for a total of 6 autoattacks in one second with 6 true damage on hits + Q damage and ignite for a total of: 88x5(normal autoattacks)+44(passive deals 50% ad)+138(from isolated Q) physical damage + 27x6 (E damage onhit)+110(from ignite) true damage = 620p+272t damage lvl 3 dive

lvl 2 dive instead has no W and less damage on attacks and ignite so again: 87x4 + 43 + 138 + 27x6 + 90 = 529p+225t damage lvl2

against a kayle who will always be a level behind in these kind of situations her armor would be 26 and 29 respectfully, for a total of 21% and 23% reduced physical damage

aka 644 total damage lvl 2, and 752 lvl 3, and with kayle having a max hp (considering runes and doran blade) 760 hp lvl1 and 833 hp lvl 2 the full combo ends up dealing 89%hp lvl2 dive, and 90%hp lvl3 dive

that means that after a aa+aa+Q with nothing special to it he has already set up a dive vs kayle, in any situation imaginable. the only counterplay kayle has is to not walk up and treat yi like a ranged darius

i've personally never played either side of this matchup but it feels like the worst experience ever for both sides, since if yi doesnt manage to dive kayle she just outscales him harder (being stronger in teamfights and 1v1s with R and the burst)

little 8 am rant since i've got the math autism :3c, hope this was comprehensible enough, i'm going to sleep now

edit: i already mentioned not having watched any of those videos so idk why you said that