<p>Sounds exactly like plot armor to me. Plot armor is often a necessity of fantasy and other fiction. However, in this case were it becomes so blatantly obvious where everything just happens to line exactly right where the character have the perfect abilities and the rule established by the plotting seem to go on vacation it becomes plot convenience. Plot armor and convenience being obvious has always been a bit of a problem but lately it has become obvious enough to jar readers out of the immersion of the story.
</p><p>Most expeditions dealing with Monstrous Rexes bring dozens of members, not six level 2s, two level 1s, and a single level 4. Given the effect on the area the level 1s certainly should have either died to exposure or at the very least passed out. The narrator even mentions that there were hundred upper class adventurers present for the Black Goliath which is the same level as the Amphisbaena, and the advantages can be balance out with the Amphisbaena's home field advantage. The alliance had just nine, two of whom bring nothing to the fight in a practical sense. Yes Haruhime can UnK, but potions and Kokonoe spam is also plot armor at its worst, there is no limit to how much it can be used and abused. And that still only gives four level 3s, who should be limited due to not being used to being level 3. The Ishtar Familia used dozens of level 3s and Phryne.
</p><p>Relying on magic swords is the epitome of plot armor, no matter how many are used they always have on more. The UMS is only going to compound that already existing issue, now the author has an excuse to claim that Bell friends can travel with him using those into the deeper dungeon, when by his own rules that is utterly false.Â
</p><p>None of the special skill of the Hestia Familia have limits allowing the author to use and abuse them as he sees fit. But it comes at a cost to the quality of the story, the struggles don't feel real.
</p><p>But the best example of plot armor in all of this is the absolute lack of any consequences whatsoever. Every thing that happens and nothing, not a single thing changes because of what should have been a harrowing and eye opening experience, everyone goes back to being exactly who they already were. And before any one says "but their new skills," let me remind you that character growth is not character development.
</p><p>This is the biggest problem with plot armor, it has the potential to destroy the tension of a story and there by ruin the immersion. If there are no stakes there is nothing to make readers care.
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