Guile
Having a really great time right now
Maybe it's all in service to not having something as stupid as 'That one blow killed him five times!' come up later?Expanding fights is one thing and adding filler to it is another thing. I am not asking for them to talk about ranks and ''power-levels'' for minutes, explaining how the shit goes on. Problem is that they were cutting small parts of canon(like the talk in the previous episode) and as seen with this episode, outright changing parts of canon.
Illya gets interested in him because while he was a non-factor previously, he suddenly fired an arrow strong enough to level the cemetery and force Herakles to block it. It is enough of a threat that Herakles turns his back to Saber and Shirou to block it. Also mind you, Illya has no idea whether Archer is a ''no-name fuck'' or not. To her, he is simply an Heroic Spirit who hides his identity.
Saber killing Herakles without using her true NP would make Illya order Berserker to either kill them or get interested in Saber because she killed Berserker while Archer couldn't. Yeah, that's the problem here. Illya gets interested in Archer while she was previously interested in Saber because apparently Archer poses more of a threat than Saber. Anime showed the exact opposite of this yet somehow Illya still gets interested in Archer.
Not to mention, that somehow Herakles heals several times faster than he does in canon. Since they added the filler part of Saber killing Herakles, they had to fix that up so let's simply boost Herakles' healing speed.
It's hard to see where they're going with this just yet.