Characters:

Main Character:

1. Mortis Nacht - This life in the magus world is his second life. Originally, he lived in a modern world without magic, where he became famous and wealthy thanks to his achievements in cell research. He began his research with the goal of discovering a way to achieve his dream goal: immortality.

Rank 0 Spells:

1. Shadow Tendril: Summons dark, writhing tendrils to entangle and immobilize targets.

2. Inferno Spark: A concentrated burst of fire that can ignite materials and cause minor burns.

3. Umbral Shield: Creates a temporary shield of dark energy to absorb attacks.

4. Shadow Dart: Fires a fast-moving projectile of dark energy to strike targets.

5. Darkness Veil: Shrouds the user in shadows, making them harder to detect.

6. Fireball: Summons a swirling, incandescent sphere of flames that explodes on impact, engulfing targets in a fiery blast.

7. Ice Shard: Forms a jagged, crystalline spear of ice that can pierce through flesh and armor, delivering a chilling wound that slows the target.

8. Lightning Bolt: Creates a brilliant arc of electric energy that strikes with lethal precision, potentially jumping to nearby enemies.

Side Characters:

1. Lethis Stygian - A friend of the former Mortis Nacht and a fellow roommate of both the former and current Mortis during the trip to the North Capital. A teen with low aptitude who was kicked out of the test right at the start.

2. Magus Haze - A stern magus overseeing the trials and selection process.

3. Magus Valthor - A seasoned rank 2 magus specializing in shadows, darkness, fire, and soul magic. Mentor to Mortis Nacht. Member of Myriad Demons Academy.

4. Kael Voss - A fellow student at the academy who befriends Mortis and helps him with navigation on his first day. He is known for his worn yet elegant magus robes.

5. Lena Rayne - A petite girl with fiery red hair and bright blue eyes, a student at the academy with a fire affinity.

6. Garrick Stone - A burly young boy with a shaved head and piercing gray eyes. He has affinities for earth, metal and darkness.

7. Jareth Windrider - A lanky boy with wild blonde hair and deep brown eyes. He has affinities for wind and darkness.

8. Magus Lyry - Kael Voss's mentor, known for her expertise in fire magic.

Organizations:

Dark Magus Organizations:

1. Cult of Eternal Damnation - Specializes in necromancy and the dark arts, focusing on the manipulation of life and death.

2. Academy of The Forsaken - Focuses on curses and shadow manipulation, delving into the mysteries of the void and the unseen.

3. Myriad Demons Academy - Specializes in the elements of fire and darkness, pushing the boundaries of known magic.

(and many others unnamed)

Light Magus Organizations:

1. Academy of the Arcane Light - Dedicated to potioneering and protective magics, cultivating purity and the light within.

2. Academy of the Radiant Dawn - Focuses on elemental control, striving for balance and harmony.

3. Yin-Yang Paradise - Practices dual cultivation of light and darkness, seeking balance in all things.

(and many others unnamed)

Key Concepts:

1. Magus Test - An annual series of tests and challenges designed to evaluate the abilities and potential of mortals, selecting a few promising ones to ensure a constant flow of new magi and apprentices to existing organizations

2. Elemental Affinites - A magus's natural alignment and proficiency with specific elements. Mortis has affinities for fire, darkness and other subcategories of these two.

3. Magus Ranks - The hierarchy of magus power levels:

a. Apprentice Ranks: 1 to 5

b. Official Magus Ranks: 1 to 9

c. Legendary Rank 10 (Rumored)

4. Apprentice Rank - The initial stage of the magus path. As apprentices progress from apprentice rank one to rank five, their connection with the world's energy particles strengthens, allowing them to cast spells more easily and with greater power.

5. World's Will - A mysterious force theorized to drive powerful magi away from the world once they reach a certain level of power at rank 4. 

6. Storage Crystal - A magical crystal used to save data and access them (basically a database). When infused with a sliver of mana, it displays stored data like spell charts and their descriptions.