Currently, us here on Earth live in an omniverse. The omniverse is a collection of multiverses that can contain dimensions, realities, and planes. There can be multiple omniverses. A collection of safe to live in omniverses is called a domain. This is a place people gather to live and create. In these domains there can be things called chains. Chains are for whatever doesn't fit into normal omniverse theory, such as things that don't exist in dimensions, realities, or planes. These chains are typically strung together like actual chains. The collection of all existence is called the Snap, due to the fact we could probably be blown out of existence at a mad god's snap of their fingers.
This exact thing has happened to people that make up the Domain, the largest and safest that tends to absorb smaller domains into their collective force. The original beings of the Domain are as old as known existence themself. They invented a way to survive dying constantly without losing all of their progress, as many others have across time since then. What they hold on to after reincarnation is what they call locks. They have many advanced locks to ensure safety, but the main locks to newcomers are things like locking your magic abilities and things like personal venom. These locks also make sure you are never without what you lock, so you always have something like your sharp teeth.
These locks are scientifically advanced but normal civilians can lock themselves with little to no effort by advancing skills. Chopping vegetables and trying to do better each time can reflect in your next life by being better at chopping vegetables, sometimes without knowing why.
Humans, and the third dimension, are known to be the top deadliest beings, even most intelligent sometimes. Something about having a physical body amongst those from chains that don't actually work surprisingly well. If you have a physical form immune to damage and have super strength and other things you can slice through anything with a sword.
Humans are divided into four different types. You are a stock human if you have the normal human anatomy and no special features besides these four variations. A stock human can have 0-256 weak points, silver in their blood or not, 206-256 bones, and a place for a natural soul or not.
Weak points are natural places in the human body that make a human weaker in every form of life. Some are simple curves in a bone or a pin prick on an organ. The max allowed for a stock human is 256. Keep in mind these can accumulate and move around in large groups. Silver in a human's blood tends to enhance natural instincts and give a certain amount of enhanced physical abilities at the cost of having less natural blood. Having more than 206 bones tend to be small bones, even microscopic, that can even form together like chainmail armor. These can also increase senses, but have less flexibility as a consequence. And lastly, a soul placement can make sure you reincarnate and/or go to a heaven. It takes up a small place in your body that typically resembles a dent or a concave curve.
Humans can lock their whole anatomy with an anatomy lock. Even humans that have natural venom can have that covered as well. There are also certain things like size caps and human strength unattainable naturally to a normal human, making that human not a stock human. Humans also can produce three types of magic. Sometimes just locking these natural magics can cover all locks needed. They typically can be uncovered through magic itself or sometimes, beings with lots of natural magics have to see entirely what their body is capable of.
The three types of natural magic are zodiac magic, personal magic, and practical magic. Zodiac magic comes from everything that affected your conception and birth, to gods, planets, elements, and whatever else. Many people's zodiac magic is a singular element. Personal magic is a new type of magic that only belongs to one person, typically never exactly seen before. Personal magic comes from magic as a base, meaning magic has a singular start and makeup that is the same across all stock humans. This magic can also be separated into a total of 256 powers, such as the base equation for controlling time, and the base element of fire.