Shadows

Shadows (그림자) are a race of undead beings that the Shadow Monarch brings into existence from defeated creatures and humans through the use of his Shadow Extraction ability.

Personalities

A shadow’s level of personality depends on its grade. Normal to Elite Grade shadows have little to no personality at all, while Knight and Elite Knight Grade shadows are able to express simple emotions like anxiety and joy. In comparison, General and Marshal Grade shadows have very developed personalities, as displayed by how Beru enjoyed watching Korean period dramas in his spare time and had his own unique style of speech.

Despite the varying degrees of personality, all shadows are fiercely loyal to the Shadow Monarch and maintain their allegiance to him even if they were adversaries in their past lives. This loyalty extends to the point that they can even override his orders to them in special circumstances.

Abilities

While some shadow soldiers have abilities unique to themselves, they all share the same set of basic powers.

Regeneration: Shadow soldiers possess incredible regenerative capabilities and cannot be killed by normal monsters, as they can completely regenerate even if their bodies are torn to shreds. However, this does not necessarily apply against some of the Monarchs, as Antares was able to permanently destroy them with his breath attack and Rakan would've been able to do the same with Beru had Jinwoo not intervened to save his minion's life.
Conversation: Shadow soldiers who are at least General Grade are able to talk. However, they are only able to communicate in monster tongue, meaning that most humans can't understand them.
Growth: Shadow soldiers are able to steadily grow in power by killing monsters in battle.
Shadow Infiltration: At the Shadow Monarch's discretion, shadow soldiers are able to hide within the shadows of other humans. While doing so, they are able to watch and observe everything happening around the person that they are anchored to. They are also able to send signals to the Shadow Monarch in case the humans they are planted on are attacked, regardless of how large the distance is between them.

Grades

Shadows are categorized into different grades, which reflect their level of strength and work similarly to how class ranks do for hunters. While shadows can level up over time by killing their opponents in battle, they cannot advance to higher grades without authorization from the Shadow Monarch. Shadows extracted from particularly powerful beings can also start at a higher grade immediately after their creation.

Basic Grade
The lowest tier, these shadows are the weakest in the shadow army.
Normal Grade
Shadows of this grade serve as foot soldiers in the shadow army and can be as strong as C-Rank Hunters.
Elite Grade
Shadows of this grade are the most common in the shadow army and are about as strong as B-Rank Hunters.
Knight Grade
Shadows of this grade are about as strong as A-Rank Hunters and can be given names by the Shadow Monarch.
Elite Knight Grade
Shadows of this grade are about as strong as basic S-Rank Hunters such as Baek Yoonho.
Commander^NV/General^WB Grade
Shadows of this grade are immensely powerful and are strong enough to contend with advanced S-Rank Hunters such as Goto Ryuji. They are also capable of speech.
Marshal^NV/Commander^WB Grade
This grade is the highest that a shadow can evolve to, making those who reach this level the most powerful soldiers in the shadow army.
Grand Marshal Grade
The ultimate rank, this grade is reserved for the strongest shadow in the entire shadow army. The shadow of this grade also serves as the lieutenant to the Shadow Monarch himself.

Shadows

Igris
Tank
Iron
Tusk
Kaisel
Beru
Jima
Kamish (Temporarily)
Greed
Bellion
Min Byung-Gyu (Temporarily)
Ant Queen (Temporarily)
Shadow Giants

Trivia

Shadow soldiers are exceedingly difficult to detect when concealed inside the shadows of other people, as shown by how Goto Ryuji and Cha Hae-In were both unable to detect the presence of soldiers that Jinwoo had planted on them even though they were both regarded as top-tier S-Rank Hunters.^[1] Only those with exceptional senses, such as Esil's father, or those with immense power, such as Lennart Niermann, are able to discern their presence.
Although most characters believe that Jinwoo summons his shadows from another dimension, this is actually a misconception. In reality, his shadow soldiers are always stored inside his shadow, allowing him to unleash them whenever he wants. As a result, he only has to spend mana to heal them, but not to call them to battle.
For reasons unknown, shadow soldiers can be immune to the timeline changes created by the Cup of Reincarnation due to the circumstances of their creation. Shadow soldiers that were derived from monsters (such as Beru and Igris) are completely unaffected and continue to exist in the revised timeline with all of their memories of the original timeline completely intact. However, shadow soldiers that were derived from humans (such as Iron and Greed) are reborn into their human forms without any of their memories of the original timeline and are able to live in their lives in accordance with the events of the revised timeline. Of note is that while Beru and Tusk would have never existed in the revised timeline as the gates would never have occured on earth, Igris came from a Gate that was created by the system the Architect and Ashborn put into place while Greed and Iron returned to their human selves as part of the revised timeline. Given that Sung-Jin woo kept his memories and powers as the Shadow Monarch to hunt the Monarchs in the dimensional spaces, it appears as though the power of the Shadow Monarch was able to prevent those that became shadows that would have ceased to exist due to the timeline changes from disappearing. This also includes the demon clan belonging to Esil's father as they also came from a gate created by the system fueled by the Shadow Monarch's power.