The world where MC is reborn is a world while the rule kill or be killed is followed everywhere it is so hollow to it's core people eat there own child which rich people kill or rape or do such things as normal and people can do nothing in a world while people are killed in this world

There are three types of cultivation which are most used

Body cultivation which makes you stronger, faster, other such things which are mainly ready on body , it is most used in the world because it is the cheapest , fastest and it mainly depends on one hardwork.

Mana cultivation which increase mana in the body and also increase mana control over it also makes you stronger as well but in a limited,unlike body cultivation it mainly depends on mana it also need talent, hardwork most mages used it and most noble family use it

Soul cultivation which can increase the size of the soul they is not much known about it people say it is useless but they don't it value

Mana heart is something which can increase the quality of the mana which flows in the body because of that body can be strengthened passively

Mana cora is something that can store large amount of mana