Chaos Beings, Magic beasts or monsters, are non-human creatures that pose a threat to society.

Chaos Beings are assigned disaster levels to estimate their destructive potential. The levels are as follows (in order of increasing threat level): D-Class, C-Class, B-Class, A-Class, and S-Class.

Legends are individuals who fight for justice against evil in the world. They protect civilians from harm against monsters, villains, natural disasters, and other threats. All work under the Apex Leauge an organization founded by the late great heroes of old that manages worlds Legends. It operates independently of the governing kingdoms. The archmagi Athena established the National Data Dex, the database that records all legend's fights, deeds, and heroics. The Apex League uses a hierarchical class system to organize its heroes, with four classes and individually numbered ranks within respective classes (classes Bronze, Silver, Gold, and Platinum). Legends can register guilds in the Organization.

Guilds are organized groups of legends that raid gates, stop invasions, defend kingdoms against demon lord's armies. They need to register by the Apex League first. Top guilds, especially those that rank highly within their home country, are considered to wield strength rivaling that of an entire nation. The leader of a guild is known as the Guild Master and with the top guilds, the Guild Master is typically a Platinum-Rank Hunter.

Bronze-Rank Legends are sneered upon as they are the weakest of the legends but comparably stronger than normal humans or demi-humans. Their abilities, however, aren't sufficient to fight even the lowest dungeon nor kill goblins along with the fact that their wage is low, their weapons and equipment were useless in battles.

Sliver-Rank Legends. The third strongest class out of the four classes. They possess above-average mana and are also capable of defeating disaster level D-Rank monsters by themselves.

Gold-Rank Legends. The second strongest class of the four classes. Veterans of war and usually take subjugation quests or take out monster stampedes.

Platinum-Rank Legends. The strongest and most prestigious class of the Apex legends. Every legend in the Platinum-Rank is equivalent to an army. Their mana levels reach the point that they can't be measured by mana detector technology. As the vast majority of legends never reach that level of power, Platinum-Rank Legends are very rare amongst the population, with only a handful per country and a few hundred worldwide. Due to this fact and the rising demand, Platinum-Ranks are highly valued wherever they go and are typically rolling in money, They can make enough cash to easily last three generations.

Mana Crystals These are one of the treasures that can be found inside Dungeons. Although they contain less magic power than Magic Cores, which come from Magic Beasts, they are normally found in large deposits throughout the Dungeons. Mining them results in an impressive income for the raiding Guilds.

Mana is essential to use Magic, it exists in the atmosphere and is divided into particles of each element. The power to control mana is largely genetic.

A beast core is a mana beast/chaos being/monster's mana core. They have an unlimited amount of uses, which makes them extremely valuable and highly sought after. The higher the classes the beast cores were, the more valuable it is.