Earth - Dinosaur era...
Life began to bloom thousands of years after the creation of the small world known as Earth in the most distant galaxy of the universe known as the Milky Way. Plants, insects, animals, and all other forms of life on land, in water, and even in the sky..
The only planet with life in the Milky Way galaxy is Earth. Why? Because the Milky Way galaxy is the universe's youngest galaxy. The universe is expanding over time, and the Milky Way galaxy is born in a remote part of the universe where no lifeforms have yet discovered it.
Because mana is abundant on Earth, the sea, land and sky is teeming with animals that could be called monsters in the future, but in this era they are called dinosaurs. Dinosaurs were the first intelligent species to emerge on Earth. They are born because of mana and they have natural control over their respective mana. Fire, earth, wind, water and etc. There are various types of dinosaurs that live in water, on land, and even in the sky.
Because of mana, new species began to emerge after hundreds of thousands of years after the existence of dinosaurs. Humans are one of those species. Humans were surprisingly weaker than other species during the dinosaur era. They are at the bottom of the food chain, they can't fight other species, they aren't strong enough to brawl like other species, they aren't fast enough to outrun their predator, they can't fly like other flying species, and they can't breathe under water, BUT.... They are astute.
Human survival is based on their intelligence; they can speak their own language, so communication is one of their most powerful abilities in this era along with unity. YES, human is united in this era because if not human will ceased to exist.
Because humans are weak, they naturally become cunning; they begin to build underground shelter so they can easily hide from their predators; they also begin to build traps and weapons so they can hunt other species.
After humans established their foundation, they began to hunt. It is ineffective at first and results in the death of another human, but humans are persistent; they are not afraid to die and want to climb the food chain, so they hunt and hunt until one day they successfully hunted their first prey, a wild boar..
Wild boars are also at the bottom of the food chain, eating only plants and occasionally humans when humans fail to hunt them. After successfully hunting the wild boar, the humans decided to butcher it because it was too heavy to transport. But they quickly regret it because it's bloody and the smell of blood spread, resulting in another slaughter in the human group. Other species smell the blood and rush to the feast, and there are different dinosaurs, wolves, tigers, and other species that came, resulting in a fierce battle that nearly wiped out the human hunter..
Because of the other species' ferocious battle, some humans manage to flee the battlefield. They are frustrated and angry not because other people died, but because they made the wrong decision. After returning to the underground shelter that they had built, the other humans who were waiting began to celebrate after silently listening to the hunter team's story... Yes, they began to celebrate because, despite the fact that many of them died, it was their first successful hunt, and the hunter team snatched some loot..