Athena in Tower Defense Game! [LitRPG]

In the regional chat channel, various discussions emerged endlessly, leaving Athena naturally puzzled, but she did not participate in their discussions.
Witty and Paopao neatly arranged the vegetables they had dragged back. Mikmik directed them on how to arrange them, and if not placed properly, Mikmik would directly intervene.
A familiar knocking sound echoed, it was the lost soul.
It knocked on the door, while Prince and Princess sat aside, staring at it with unfriendly eyes. After the last incident, they already knew that the lost soul was the master's guest, so they did not obstruct its knocking.
But the lost soul exuded an aura of darkness, making them very irritable, almost wishing to rush up and fight with it.
Athena opened the door, only to see the lost soul staring at her unfriendly. It was too lazy to maintain its image now, disregarding its childish voice: "You weren't here yesterday!"
This was not the first time the lost soul had been given the cold shoulder. Seeing its irritable appearance, Athena took out a piece of dried meat from her backpack and handed it to him.
"Why didn't you just put the parchment paper in front of the door?"
Speaking of this, the lost soul got angry, fiercely biting into the dried meat and saying, "The text on this parchment paper will disappear automatically after a certain period!"
Athena nodded knowingly and gave him another piece of dried meat. Taking the information from the other party's hand, she unfolded the parchment paper and read it loud enough for everyone to hear.
"The darkness is awakening, its loyal followers are starting to move frequently."
It was again one of those incomprehensible phrases. The information was brought by the lost soul, and it surely knew more than what was written on the parchment paper, but it either couldn't say or couldn't say much.
Taking out another piece of dried meat from her backpack, she asked Witty to bring a tomato and handed them all to the lost soul.
Returning the blank parchment paper where the text had already disappeared to him, she said, "The text is not clear, maybe you can make it clearer."
The lost soul looked at the food piled up next to it, then at the parchment paper Athena handed back, pretended to make some changes, and handed it back to Athena.
"Merfolk!"
Behind the small figure floated a black spherical space, swallowing up all the tomatoes and dried meat. The lost soul's anger was replaced by joy, completely different from when it came, and it happily left. It didn't expect Athena to return the parchment paper to it now.
Rolling up the parchment paper and storing it back into the space, the lost soul could still write more detailed information.
It just didn't want to, nor did it want to take that risk. Athena had no comment on this, but fortunately, the other party was a foodie. When she gave him roasted mushrooms before, he enjoyed them a lot.
If things go as expected, this will be probably the monsters attacking the towers, the hut and her in the next round or so. What troubles Athena is not the opponent's high attributes and level, but the fact that merfolk are people therefore intelligent-level units.
This means that merfolk have intelligence akin to humans. The reason players can defeat monsters higher in level than themselves, besides relying on various types of towers, is because most monsters fight on instinct, while humans know how to use tools and traps.
This is the unique intelligence that humans have compared to ordinary monsters, and now they are facing merfolk who are not only stronger than them but also possess equal intelligence.
Back in the wooden house, Athena began to ponder whether she should go and search for the goblin instance today. After all, the system's notification hasn't come yet. To prevent accidents, she chose to wait.
While waiting, Athena cooked a pot of vegetable porridge, and she and her companions enjoyed the delicious meal by the fire.
As the clock's hands reached twelve, amidst the anticipation of numerous players, the system's notification finally arrived, albeit late. However, the notification wasn't about tomorrow's tower defense time.
Upon hearing about the system barrier, Athena rushed out of the door and into the courtyard.
The system barrier was encountered by her when she first arrived in this world, a means by which the system restricted their exploration beyond.
In this dark world, Athena stood in the courtyard, looking out into the distance. One by one, the barriers that stretched into the sky in the forest lit up, gradually becoming visible. Emitting a faint glow, they were dazzling in the darkness.
They seemed like towering walls that separated players from this world. And now, they were slowly moving backward, revealing a glimpse of this world's iceberg.
At the same time, those monsters that had been isolated were now appearing within the players' activity range. They excitedly crossed the barrier and lurked in the forest, patiently awaiting the arrival of tomorrow's daylight.
While the barrier restricted players' freedom, it was also a means of protection...
And now, these monsters that had been released were given 'rations' by the system for these three days.
If they eat well, they become fat...
If they don't eat well, they become the rations!
And on Athena's system panel, the notification for the regional battle was still displayed.