I followed you on accident but yes I suspected he was the killer due to him killing very leisurely without thought. As well as his sociopathic nature. That does not suit a random NPC that killed a random person before the game starts. Granted maybe he killed that villager out of self defense since the villager did try to kill Bada’s group. But then it wouldn’t make sense since we saw how cold Doha was when killing that man. It looked like he knew what he was doing. It also makes sense since Doha can somehow keep the killer at bay.
You're right it could be a third party, but from my perspective it's simply a matter of how the game's code is written. I won't go too deep into spoilers but Until Dawn is another game that follows this setup.
Doha's identity as the killer was something that was supposed to not be revealed until the true ending, with Bada accidentally discovering that truth early. So the game's coding prior to this was set so that the killer was set to kill the party, with Doha not being an exception in order to maintain the plot twist until the end.
But honestly I'd totally believe it if God or some other entity just wanted to fuck with Doha and give him a taste of his own medicine
I think it has to do with Nam doha, if the villager remembers being killed by what was supposed to be one of the npcs, then he knows that the rest can't be trusted either (even if the rest of them are just normal dudes). Either that or a psychotic breakdown from being stuck in the game too long.
It's a bit hard to tell right now which is the truth until we get a bit more insight into what the villager has been doing between each game session, it'll also tell us if they were in possession of a cassette tape as well
1. Nam doha is the og killer, this can be inferred by the fact that he kills off the villager before the events of the game start. He is also an npc so he can't leave the game like Bada can (this is the important part)
2. The current killer is basically just a hollow copy of him with no memories and no way to distinguish Nam doha from the rest of the group (which is why he dies as an npc before)
3. The villager is a playable character who has been stuck in the game for much longer than Bada, he was killed by Nam doha for trying to warn the group and shows up again at the tunnel after failing to find an exit
4. Nam doha is using the extra cassette tapes to hinder Bada's progress, as soon as Bada is about to escape he is going to use the two cassette tapes to revert their progress back to when they first started working together. (I think Bada mentioned that extra cassette tapes can be used to override other ones)