This has been cooking in my mind since I watched the first 3 episodes, just wanted to know if there are others who think so as well.

TLDR: Homelander kills Ryan that pushes Butcher over the edge, same way how in the comics Black Noir killing Butcher's dog pushed him over the edge.

Full Theory:

So when Ryan goes to meet Butcher, that dog cookie jar is shown a lot. I noticed in the episode that when Butcher threw away the drugged cookies, he forgot to keep the lid on the jar, which makes it seem like the dog has no head (as if decapitated).

Instantly, the camera shifts a bit and it shows the headless dog jar in the foreground while Ryan is the background. And Ryan and Butcher go on to play the 3rd foosball game.

BUT, then the scene shifts to Anika's interrogation where Homelander swears on Ryan's life that he won't do anything to Anika, which he obviously didn't keep as he killed her.

In the comics, Butcher was pushed over the edge (or at least that's what I read in wikis and on reddit) when Black Noir killed Terror, his dog. That's when he becomes a complete maniac and crazily hellbent on eliminating The Seven and all Supes.

I think, Ryan replaces Terror's place here as hinted by the camera POV, and Homelander (whether accidentally or deliberately) kills Ryan, which makes Butcher completely abandon his sanity to go after all Supes as he does in the comics as well, becoming the final antagonist of the series just like the comics.

Would love to discuss with y'all!