Their plan was very simple. First, they will kill the normal ghouls as much as possible using the explosion caused by the red ghouls when they die.
Then, as they had already applied oil on the wall, that would cause the wall of the tower to turn into a firewall and a killing machine for ghouls.
Arya knew this would be effective because he knew, that the beast in the tower, especially in the tutorial trial had specific commands inserted into their brain for them to function in that specific manner.
The ghouls in this trial had two such commands. The first was to destroy the crystal present on the tower at all costs, and the second was to kill all humans present. It doesn't matter if their kin dies in the process or they themselves die, all they need to do is fulfill these tasks assigned to them.
Using that to his advantage, Arya created the plan. As both the Crystal and the humans were on the tower, every ghoul would climb the tower. And since they don't care about their or their kin's life, they will not stop climbing the tower. Even if it turned into a firewall.
And the plan worked like wonders, as the ghouls started climbing the tower without caring about themselves. The normal ghoul died easily from the fire While the red ghouls took a little time to die, but they too soon died and even exploded which killed many other ghouls.
As for the Six General ghouls that were present on the trial. As one would expect from a Higher rank monster, they had higher health points and stronger defense. So, they didn't die because of the firewall, just got hurt. But as soon as it reached the top the Arya and others easily killed it.
"What? Such things exist in the tutorial?!" Rohan shouted in shock, this sudden shout also caught the attention of Arya and Aetherius.
"What happened?!" Aetherius asked.
'Should I tell them, this is a new discovery? Wait!! They must have received it too, right?! They killed so many of the ghouls.
Wait, Is this the reason for their strength? These bastards monopolized this alone they didn't tell this to anyone.
If we all knew about it, many people in the previous stages would have survived.'
Rohan gritted his teeth as he thought of all this.
Though he was half right as these stats play a big role in the strength of both Arya and Aetherius. But that's it, there are many other factors too.
"I got this free stats thing," Rohan said expecting a little bit of surprise from the other two. But alas! He only received an affirmative nod. As if it was expected by them.
"Well, good for you."
"Use them well."
This is the only response he gets from both Arya and Aetherius respectively.
Such a response angered Rohan, as they were acting like they didn't care about what happened, but he calmed his anger by thinking about his plans.
'Just you wait, you selfish bastards. Just wait!'
As the Ghouls kept dying in the fire for a while, then the fire stopped, but the fire killed most of the ghouls, Arya and Aetherius jumped off the tower as soon as the fire died down and started killing all the remaining ghouls. And the monster wave ended in a few minutes.
As soon as the wave ended, like all the previous times all the monster corpses that were present disintegrated into blue particles, and the whole area was restored to its original position. Also, the tower which was blackened because of the fire also returned to its previous state.
Since their strategy was a success, they used the same strategy in all the other waves, though as the number of ghouls was increasing with each successive wave, so the number of survivors was also higher. But that was not a problem for the party. So, they easily defeated the monster waves.
During the last wave, the ghouls appeared from all four cardinal directions, but that didn't affect them much since a large chunk of the ghouls were killed by fire and the rest were finished by them. So, the ninth day also passed.
As it was night, they decided to do what they were doing for eight nights, two people would sleep while one would stay on night watch. And today it was Arya's turn to stay on the night watch. So, both Aetherius and Rohan started sleeping.
Everything was like usual, but something different happened today as after every two hours after the monster wave ends, the next one starts. But nothing happened today.
This made Arya frown, as he didn't know why no monster wave was happening. So, he decided to wake the others up.
"Hey!!, guys wake up!"
Arya said while shaking both of them to wake them up.
"Huh!, are the monsters here?!" Aetherius questioned while Rohan had his guards up listening to Aetherius.
"No, they didn't that's the problem!" Arya replied
"Huh?!, why's that a problem, maybe there's still time left or something like that."
Before Arya could even say anything an announcement rang.
[Congratulations on surviving the nine days of the nightmare difficulty.
As for the last day, there will be no monster waves, only one final monster wave will be there today.]
"Well that's answered your question now let me sleep, I need to fight tomorrow morning." Aetherius said with a cheeky smile and went back to sleep
"You--- forget it, you deserve a rest," Arya said and didn't disturb Aetherius and let him sleep.
Then he turned towards Rohan who was just watching these two silently.
"Well even though the announcement mentioned we can rest, but this is the tower and we can't trust anything here as you can die any moment, so we will continue our night watch. It's your turn now, but wake this giant after two hours." Arya said to Rohan, who agreed with it.
As Rohan was on a night watch, the other two started resting.
After around two hours Rohan woke up Aetherius, and told him what Arya said. Though still grumpy Aetherius agreed to the night watch since he understood what Arya meant.
Aetherius stayed on the night watch for the next two hours, and the sun was starting to rise since it was around six in the morning. He woke up the other two and they started doing the discussion.
"Since this will be the last wave. We will have to give our all. From previous waves. We know the Ghouls will come from all directions.
They will have all the variants, the red ghouls, the ghoul general. And I think the final Boss will also be there."
As Arya mentioned the possibility of the enemy from the last wave, both Aetherius and Rohan got tensed.
"So, what's the plan, the firewall one right?!" Rohan asked Arya.
"No, the plan will be different. Though the firewall plan is good. We will not use it this time."
"Huh?!, what do you mean?! How are we going to win? By killing them fighting head-on?! I know you both are strong but even you have your limits." Rohan shouted at Arya as he couldn't understand why Arya didn't want to use such an easy and good strategy.
*Kuggh!!*
Aetherius seeing Rohan's act slams a karate chop on his head, to shut him up.
"Why did you hit me?!, you should support me?!" Rohan asked while holding his head.
"Shut up, till now Arya's all plan helped us, so he must have reason to and second thing. He is the strongest of us three." Aetherius countered Rohan.
This put a smile on Arya's face, and soon he described the new plan to both of them.