I'm thinking of an alternate scenario where Daru is the actual villain.
Super long post ahead, because this is essentially a short fanfic with lots of incorrect information I have no plans on verifying by reading this darn manga.
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Instead of this heroic bastard that doesn't work, Daru is actually thinking of taking Athena for himself because he still hasn't moved on from the death of his former lover. Once Athena invited him to the party, Miliara immediately realized what's going on because she's the most intelligent member of the party, she knows a lot of people and she knows a lot that's happened, and she actively seeks out information about Daru. But even so, Miliaria doesn't know what Daru is going to do, she can't read him, so instead she acts like she knows nothing until she knows definitively what Daru is going to do. So when Athena proposed to kick Est out, Miliaria saw it as an opportunity to rat out what Daru is going to do. In this alternate timeline, while Daru seemed uninterested, Miliaria immediately saw how his eyes lit up for a moment after hearing Athena.
After kicking Est out of the party, Miliaria would maintain minimal contact with Est, in order to know what he's up to and understand how she can use him as a pawn if it ever became necessary. Miliaria doesn't really like Daru because of how much he eyes Athena, but she can't do anything about it because Athena's words are final as the leader of the party. And Athena can't see how much Daru is looking at her. Miliaria can't just spell it out because Athena still wouldn't understand so the best Miliaria can do is keep Athena safe.
Anyway, Miliaria saw how powerful Est became after getting kicked out so she gets into direct contact with him and apologized immensely and told him her plan. That's before Est saw Daru and Athena in that fateful position, so Miliaria effectively won Est's trust.
Sooner or later, the party gets a mission that's super vague and open-ended, which raised Miliaria's alarms to 11 but Daru seems too into it. By this time, Daru has completely won over Athena's trust enough that he was able to bullshit his way into making her accept the mission. This is bolstered by the fact that Miliaria agreed, but for different reasons. Miliria knows this mission will be when Daru strikes so she makes a move to have Est prepared for any evetuality. Daru is suspicious but in his mind, he has the perfect plan. Maybe out of sheer desperation and desire.
Anyway, once they got into an uncharted part of the forest, Athena and Daru would always find Miliaria getting multiple nightmares in her sleep. So whoever's on night watch always see her wake up in the middle of the night and spend some time together. Until one particular night when Miliaria gets another "nightmare" which she woke up from herself. She can't move her body in any way, and her head also felt like it's splitting apart.
It would turn out that her "nightmares" aren't nightmares but delayed magic that sends immense phantom pain all throughout her body to forcefully wake her up no matter what sleeping agent's been administered in her body. She can't move her body but she can move her lips so she's able to chant magic to create an earth golem that could envelop her and move her body for her. Her bag, all her clothes, and nearby trees were all burnt to the ground, including several antidotes she prepared just in case. Those were well hidden but the fact that Daru didn't take any chance and just burnt everything shows how experienced he is.
She doesn't see Daru and Athena but she has several countermeasures for when that happened, including faint mana traces put on both Athena and Daru with different signatures to make it easy who she should follow. The mana traces were faint but has varying degree of strength when fresh as opposed to older traces. They haven't gotten far away.
Miliaria shot a massive fireball in the sky that could be seen from the nearest town, a signal to Est that something's going on.
She went after the traces even without Est being there but she knows that he can also read the mana traces like she does. Miliaria trained for this moment so she has flawless control over the earth golem and soon caught up with both Athena and Daru, who has all his limiters removed.
Miliaria opened with her most powerful magic (I don't know what that is but it should be powerful enough to force Daru to drop Athena and focus on defense), forcing Daru to drop Athena and focused on defense, during which Miliaria engulfed Athena in thick layers of earth and some metals for safety. Miliaria then evoked massive earth spikes around Athena to destabilize Daru's footing and opened up another powerful spell to detach Daru from Athena. Once she confirms that Daru's backed off, she makes a run for Athena but in doing so, she gave up the initiative to Daru, who now doubled back with immense speed and power. He slashed at the earth golem, now in front of Athena's cover.
It was easily cut but Miliaria was able to eject herself from the back and create another earth golem, then another, then another to distact Daru while she moves Athena underground while bombarding the place with mana to hide Athena's mana trace from Daru (Miliaria knows that Daru can't see mana trace, but Miliaria knows that Daru know some stuff she don't so she's not taking any chances). The reason why she had to get to Athena is because moving a person underground is a delicate task that requires precision to not crush the person but still allow them to breath but also Daru would not allow that to happen and would deperately cut into the earth to bring Athena out, bringing them back to square one.
Athena's whereabouts are now unknown to Daru. It's now that Miliaria also removes her limiters and unleashed powerful spells after powerful spells against Daru, who cut almost every single one slower than the last. Daru has not used his full power in a long time so the strain it puts in his body after laying dormant in so long is showing its signs. More and more spells hit Daru as time passed. However, the same can also be said for Miliaria, who felt her mana circuits being overwhelmed for a moment, a moment Daru used effectively, dodging the spells that no longer had any direction, and stabbed Miliaria's golem with everything he has.
Miliaria was able to dodge the exact same way as before but she underestimated Daru's power, which extended the reach of his sword to reach her. Before she could fully disengage, he was able to stab her in her left shoulder, which almost cut her left arm entirely. Miliaria's nose were already bleeding and the veins in her head are almost popping with how hard she's working her mana circuits. She can't afford to lose any blood here. So she made the choice to just cut her left arm entirely and burned the wound to stop the bleeding.
However, by the time she's done, Daru's already in her face, ready to pounce. She once again tried to eject the same way before but Daru is faster. He made a side sweep that threatened to slice her golem armor and herself in half. So she focused her entire being on defense by releasing massive amounts of mana from her entire body at once, overwhelming her mana circuits even more. The resulting shockwave destroyed her golem and threw Daru far away. It also made her mana circuits inoperable so now she can't conjure magic until she's healed.
The shockwave momentarily rattled Daru's head, probably gave him a concussion but it was only for a moment. He used an enchanted artifact to heal himself right back. And once again went after Miliaria, who by now, is just a frail girl who can't move or even use magic.
Daru probably didn't plan on killing Miliaria, just make her dead enough to not fight back but alive enough to give Athena back to him. Whatever the case may be, it was during that time that Est showed up. He plowed through the trees and released a powerful spell that not only dealt damage but also immobilized Daru (I'd like it if the story has some electric based magic, so Est could taze Daru for immobilisation). Daru was blown away and couldn't land on his feet a few meters away. Est gave Daru more status ailments to prevent him from moving for a while, while he treat Miliaria. But for some reason, Daru got up and charged straight towards Est.
It seemed that while Daru was surprised by Est's sudden appearance, he wasn't completely caught off guard. He now wore several articles of clothing that promotes status correction. His sword also changed, from the previous iron sword to a black longsword with runes glowing in its taper. It seemed pretty specialized to fight someone who can grant status ailment. It seems that Daru also took notice of Est's growth.
Est tried to retreat with Miliaria in tow but once the sword was within a few dozen centimeters away from Est, it released a shockwave of black mist, which broke every enchantment spell Est casted on himself. This forced Est to use conventional spells that could repel Daru in that instant, a powerful explosion at point blank range. All three were injured but Est could heal himself and Miliaria right back. However, for some reason, Daru refused to move after.
It was now Est's chance. While he healed Miliaria's external wounds, he still had to heal her paralyzation. Est covered Daru in multiple thick layers of earth before proceeding. He then found out that Miliaria was given a slow acting poison alongside a strong sleeping drug. It was probably to ensure that the mana within Miliaria's body doesn't get out at once and attract unwanted attention from surrounding magical beasts. So instead Daru gave her a slow acting poison that would naturally diffuse the mana inside Miliaria slowly enough to ensure that both Daru and Athena can get away before magical beasts hinder his way.
But thanks to it, Est had ample time to manipulate his healing spell to counter the poison. Although, parts that are already dead were unsalvageable. Est looks at Miliaria's blackened feet and decided to cut them off below her knees and healed the resulting wound. The procedure proceeded smoothly after but Miliaria couldn't wake up. That's understandable. Her mana circuits are almost destroyed and her body needs lots of rest.
Est got up and looked for Athena but he couldn't. But he saw a faint mana trace not far from where they are. That's probably where Athena is, but for now he has to deal with Daru.
He once again enchanted himself to the very extent of his power to match Daru. He spared no expense and used his most expensive gears, in order to once and for all, kill Daru.
It was right on time, as Daru finally awoke and destroyed the earthen cover. There was no talking, they only shouted at each other the other's name. The battle lasted for a few hours until finally, Est was able to defeat Daru and kill him. Est's own mana circuits are overwhelmed beyond belief, but he finally managed to do what he's supposed to. Est brought both Miliaria and Athena back to the closest town and rercuperate.
A few months later, Athena and Est continued to venture together as exclusively two-person team while Miliaria retired as an adventurer due to the injuries she's suffered. She's lost her entire left arm and both her feet are dead. Her right eye is also going blind fast. But she was never depressed. Instead she saw the wrong in her ways. She decided to stay in the royal capital as a teacher for the royal court magicians, especially the offense magicians. Because she doesn't know anything other than offense magic. Miliaria is incapable to using any magic that's not classified as offense magic, that's why she had to resort to attack-type magic to perform other tasks. Like delayed phantom pain and having to burn her wound instead of healing it, or detoxifying herself from the poison and the sleeping agent. Because of this, she's always had to rely on white magicians, but on the occassion that Est was kicked out, she became vulnerable. But also because of that, she has unparalleled firepower in her offense magic.
When Athena asked why Miliaria had to bear the burden of dealing with Daru and didn't push Athena further to not accept the old man as a party member, Miliaria was ashamed. Miliaria was like Daru, she also hid her power. But like all the other powerful people out there, this strength became her downfall. She severely underestimated Daru. She thought that if she unleashed her true power, then not even Daru would be able to stop her. This is where Daru overmatched Miliaria, because he never thought he's more powerful than Miliaria, so Daru could have almost killed her if Est didn't arrive. It was because Daru didn't know exactly how powerful Est became that Est had a fighting chance against him. But if he did knew, Miliaria was confident not even Est could defeat him. Miliaria was full of herself, and she failed to see that. She thought she was so clever that not even Daru could outsmart her, and that everyone's playing at the top her hand. That was how complacent Miliaria became. So this rude awakening was very much needed before she loses a lot more than limbs.
And so Athena and Est became one of the most popular heroic duo team in several continents, venturing deep into the unknown like no others. And their name would be remembered in the annals of history thereafter, while Daru's name is completely forgotten; thanks, in no small part, to Miliaria's intervention in the national libraries and the kingdom's collective knowledge.
Athena, of course, also became powerful out of sheer desperation not to repeat her previous misgivings and to make sure not to burden Est too much. She became an effective leader as well as fighter.
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Now, the reason why I'm not writing this in a better format, like a proper story, is because I don't know exactly how the magic system works in this manga. I also don't know the culture or the deeper personality of each individual. I don't care about the dragon girl altogether. That bitch can croak and die for all I care. So I made a lot of assumptions and I'm not super comfortable making a full-blown fanfic based on wrong perceptions. At the exact same time, I really don't want to read this dogshit to understand the things I don't. So it will probably always stay as this short story that's super far from the source material. But I still want to write it somewhere and I think this is a good place to do so.
I focused almost entirely on Miliaria because I thought her position in all this is the most interesting. Daru is a villain; Est is the betrayed party, which is a story that's already been repeated a bajillion times before; Athena doesn't even seem to have a personality and I just frankly hate how hypcritical the author made her. I know the least about Miliaria's personality however I know that she loves Athena and that her position is the most unique in all the cast members.
