See my theory is Yahyul performed something similar to what we saw in the mock battle. Yahyul probably blended into the crowd and waited for the opportune time to attack the enemy commander. Battlefields are often hectic and messy, so it's not too much of a stretch to say the ppl wouldn't recognize someone they've only seen once (also he has already shown how he's good at masking his personality/general vibe). Furthermore, since the MC got injured protecting Godo, he probably didn't see who attacked him and just the attack in general (we see MC was facing Godo when he was injured, so we know he got attacked from behind). Godo caring for the MC and feeling guilty/responsible for what happened probably would have focused on the MC's well-being over the battle at hand. It was even stated that Godo's hatred for snakes stemmed from that incident and he never got his revenge. If he didn't know who stabbed the MC and just that it was a snake, it would also make more sense why he hates them all so much (the idea that every snake he meets could have been the one who severely injured his friend but he doesn't know who and they might do it again, would make a person tense/paranoid (this also makes sense why he makes comments to the MC about getting stabbed in the back)). I also can't help but be fixated on the secretary's comment on Yahyul's performance in war and how he was extremely terrifying (I interpret that as a brutal killer). So we know from that alone, he showed extreme skill and battle prowess during the war. Finally Yahyul low key a psychopath (don't get me wrong I love him), but 1- he values logic over everything and actually has a hard time understanding why others would let emotions cloud their judgement (we see this in the group cadet discussion over the tale of the snake who manipulated the rain for their lover). So his thought process was probably, it's war -> war has consequences and casualties-> there's no actual bad will/intentions because he was a soldier and it's a soldier's job to kill -> no a big deal/problem (pretty much: it is what it is, no hard feelings). and 2- he's lied to the MC from the beginning and when confronted still lied/gaslit him until he couldn't, soooooo I think this man has very much the opinion that he's smarter than everyone else and him getting caught isn't even a possibility. (If he did do it, it will probably come out via betrayal by the secretary/father who has an issue with the relationship and is trying to push the MC away kind of thing - at least that's how these things usually go)
I like what you're thinking, tho I don't think I can take that much angst ╥﹏╥ haha. I can def see Yahyul having the logic of the soldiers at war since yeah it's war. Tho it would make sense that Godo would assume that it's a snake since they were against the serpents (still doesn't excuse him being speciesist/racist btw). The amount of angst if it's true, though I wouldn't really blame him since he was going for the enemy commander & Hyeon got in the way. The amount of much needed conversation after the revelation tho XD
I completely agree with the Godo statement, man needs to shut up and chill with that sh*t. It's his low-key sh*tty personality that makes me think he didn't see the person who attacked them on the battlefield though (or hasn't seen the snake since). Whether the war was over or not, I can't see him with his hateful personality letting the snake live (but we know he didn't get his revenge). He's 110% the type to do some shady sh*t where he would give himself the opportunity to k*ll the person and then very fakely claim it was a training accident or something.
I think the only way this plotline makes sense is if Godo was purposely riling them up to test how they would react once outside of their controlled training environment. And they failed big time. They are working on bringing peace and they let just one person come in and influence their attitudes towards each other. Two things lead me to this theory. 1.) Hyeon also harshly scolds them all for failing. 2.) Godo is never seen being this nasty afterwards.
Yeahhhh, I'm going to need to see WHO cut off our MC's wing because I have a sneaky suspicion that it was Yahyul (he says SO many sus things) and it's making me an emotional wreck. I'm just trying to appreciate the slow burn and then more evidence keeps coming out pointing to Yahyul as the culprit it's giving Yandere