List of Demons in Castle

Many demons(referred to as “Evils” in the Castle Prologue, creatures in the main cannon and many individual names by the fanbase) appear in the Castle series, spanning many subtypes, some of witch appear to be separate stages in the life cycle of on "species"

Dragons
The Dragons have made their appearance only twice in the series. The first appearance was in Castle I. Etrius single-handedly killed this Dragon with the use of a sword as he slid down its back out of the Castle. The remains of the Dragon were destroyed when it was enveloped in an eruption of white light, though this destructive end was later replaced by a flashback where Etrius rips out its spinal cord with his katana and the dragon simply perishes, its glowing eyes fade into empty, dark sockets. The Second Dragon appeared in Castle Repercussions Part D2 as those who had been left behind attempted to escape in the last chopper. The Second Dragon only briefly appeared before the end of episode and had a slight variation in appearance, but many fans agree that its arrival sent a chill down their spine.

Drones
The Drones have appeared in Castle II, III, and Repercussions. The Drones are also called the "Undead", the "Zombies" (in the Prologue), and the "Freaks" (Sergeant Mullins' generic term for all the Evils). As far as has been revealed, there are three types of Drone. The first and most common type are seen regularly fighting the soldiers. These creatures have glistening white fangs and glowing white eyes. They apparently evolve into much more muscular and demonic creatures called Hunters. These Second Phase Drones are seen in Castle III as one crashes through the wall and slams Private Ray Williams into a wall before being shot down. The evolution process is witnessed by Ray later in Castle Repercussions. The Third Phase Drone is not technically an evolution and might be classified as a completely different monster. Due to the stick-figure animation, this is uncertain. These monsters have jagged black teeth and deep, nearly empty eye sockets. They appear to be sleeping in Castle Repercussions until there is a blast followed by a loud ringing sound. The monsters then stand up-right, apparently snapping there bones into place. This may be due to the fact that they have been sleeping for an untold amount of time.

The intelligence of these monsters varies with each type. It seems as though the Drones and Hunters are similar in intelligence. They simply see a target and attack it without any regard for themselves. The Third Phase Drones are seemingly completely stupid, only capable of reaching out to the things around them and latching on tightly, though this may be due to the fact that all of them had just woken up from a deep sleep and had all just set their bones back in place.

Hawks
These flying demons appeared in Castle III and Castle Repercussions. They have no visible mouth and have the same white glow in their eyes as the First Phase Drone. They have a meaty torso and muscled arms that resemble humans. They have large claws and giant bat-like wings behind their shoulder blades. Instead of legs, they have a long, serpent-like tail. These monsters are strong enough to withstand a bombardment bullet wounds and are seemingly strong enough to lift a human with ease. Their intelligence seems slightly lower than the First and Second Phase Drones.

Puppetmaster
Nothing is known about this mysterious being other than its uncanny appearance in Castle Repercussions Part D1. It is seen briefly as a gangly creature, dropping down from transparent tentacles growing out of its back that it uses to walk rather than its thin legs. Speculation is all the fans have as to the origins of this creature. One theory is that it was Etrius, who may have mutated due to his contact with the Artifact. This theory holds very little water due to the appearance of the Puppetmaster's vicious tentacles in Castle III. Another theory is that this creature was what was released from the Orb. This also is speculated as improbable. The monster would have to have been instantly teleported to the sublevels of the Third Castle in order to perform its deadly acts later on. It is also unknown as to how many of creatures of this type exist. Evidence says that there is only one, but there is no statement to confirm this.

Strategy
The evils are generally shown as attempting to overwhelm the protagonists through sheer weight of numbers; a good example being a soldier being killed on the bridge because he was unable to kill all the attacking zombies before they reached him. A good soldier skilled in ranged and melee combat can commonly kill hordes of the creatures before having to flee (although this may have been their original intention) or be slaughtered, as demonstrated by Mullins in Repercussions Part C. Drones are shown as being relatively easy to kill, if it werent for the fact that they are very agile and can scale walls. Boomer even says that "They break so easily." Hunters (the demons who are basically beefed up versions of drones) are somewhat harder to kill but will drop under concentrated fire. Hawks(hunters with wings) are shown as very stubborn and take forever to kill. Puppetmaster tentacles have not been injured in the series so far, but severing the tentacle would, in theory, kill it.