I only came here looking for the early toc, but I suppose I might as well contribute to the discussion while I'm at it.
I don't think the idea here is just to have a betrayal, but to create tension. Compare a character being told that they have a severe heart condition that could kill them at any moment vs a character just suddenly dying of a heart attack with no warning. A sudden death out of nowhere is more shocking for sure, but if you tease it beforehand you can build up tension by making the readers wonder if or when that heart problem is going to come into play. Any time there's a situation where that character has to exert themselves the readers will be on the edges of their seats wondering if this is going to be it for that character. Similarly by planting the idea of a traitor in the readers' heads the author can make them start looking at the characters with suspicion. Is someone actually going to betray the group? Who is the most suspicious person among them? I think this kind of an approach is more interesting than just having one of these characters we've barely met suddenly turn out to be a traitor. Shock value only gets you so far.
There's also another angle to this in that the idea of betrayal was brought up by Tylty as the explanation for why him and Mylty failed the test the last time around. Instead of trusting each other and working as a team like Velou's group is doing, the previous hunter candidates were all paranoid about each other and failed. I think this serves to highlight that Velou and the others have the right idea, especially since if they succeed it will result in every single candidate passing the test, which would be the polar opposite of what happened the last time around when every single candidate failed. If you just take the rules at face value and tackle the exam like a normal game of cops and robbers you are guaranteed to lose. None of the newbies should be able to evade two professional hunters for two hours. You can only win if you pay attention to the rules and work as a team to plan around them. The handful of people who made the seemingly counterproductive decision to not run away at the start are the ones who actually know what they're doing. Tylty and Mylty running away shows that they don't have what it takes to be hunters just like last time, which is why they'll probably change their minds and redeem themselves by rescuing everyone at the eleventh hour.
The mayor reveal being too sudden I kind of agree on. I think the reason it happened so early was probably because the first volume needed some sort of a twist that would make the audience curious about what's going on. I guess you could also see the mayor tailing Ironworks together with the Rest List members as a way to set up a quick final boss fight in case the axe came down. The little red riding hood faces the big bad wolf, Debonair gets to fight the potential source of her heat curse and Velou has an axe duel with the mayor. That would actually make for a pretty solid finale as far as rushed endings go, but I'm hoping the series manages avoid that fate. I've been enjoying the series ever since the Red List showed up and would like to see it stick around. Things aren't looking too good at this point though.
I agree with the tension, its call 'BOMB under the Table' scenario, or RUBBER-BAND getting stretch, its to maximize the impact.
-But, thats still 'wrong' on 'maximize' betrayal subplot. I want hint there is something wrong happening, or not all action according to plan (someone die, like aizen, hehehehe thats absurd example), then in the end reveal there is betrayal among them but we still dont know who is doing it. Then velou had flashback with the veterans who fail last time because the same thing happening.. So we got the shock, then after that we follow the same scenario like this chapter and after. We still can try to guess who, etc. So in the end, we still get the tension Plus the shocking part.
-somehow, its ease the tension, because, i feel like VELOU already prepare it. We the reader knew it, the characters 'knew' it too. Understandable, right? Its like if you do it, do it right, or dont at all.
But now, i am more surprises if there is no betrayal after being told in OUR FACE, thats kubo-level troll. All participant is in the same page, all buddy-buddy., The negative aspect is, no conflict among newbie.
But hey, thats just my opinion
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Not good company to had.. I still sad about golem hearts, i love the one shot, but the direction of the series all goes wrong (adventure ala One Piece to naruto-MHA-BC route).