The Core

The Core was an enigmatic, biomechanical hive mind from the dimension Amphibia that served as King Andrias' true master.

Appearance
The entity's original form was a multi-eyed spherical robot with robotic tentacles and glowing orange eyes with lighter shaded pupils. In terms of size, it was larger than King Andrias. This form was seemingly connected to Newtopia's castle because of the various wires that were connected to the walls and the presence of its eyes in different locations of the castle for communication. One such eye was even located in Andrias's crown.

After possessing Marcy Wu, the Core renamed itself as Darcy (meaning "Dark Marcy"). Its current consciousness was represented by a dark helmet with four branched gill-like horns, ten eyes, and a long wire connected to it. As Darcy was possessed by it, she wore a matching outfit with a long red cape and additional orange eye marking over her stab wound. Over time, the helmet's eyes changed into diamond shaped eyes while her three larger eyes gained small red pupils.

After Darcy's defeat, the Core's next body was an animated version of the Darcy helmet with six legs to wander around. After possessing Amphibia's moon, it gained a massive orange eye surrounded by dozens of smaller eyes and exposed oranges bright wires.

Powers and Abilities
Being a collection of Amphibia's greatest minds, the Core possessed their combined intelligence. Given that they had centuries worth of knowledge from Amphibia's scholars and rulers, they were arguably the smartest entity in the world. They possessed an extensive knowledge on advance technology as well as battle strategies which served the rulers of Amphibia well in their invasions over the centuries.

However, the Core's intelligence appeared to be limited in its Darcy form, as it adapted some of Marcy's forgetfulness. This was shown when Anne outsmarted Darcy, saying she could not kill her because if she did, it may become impossible to use the box.

The Core could project digital imagery from its eyes to create virtual realities within the castle, allowing them to distract their enemies.

While it was in the castle, the Core (in its Darcy form) could control mechanical "tentacles" from its original body to easily overwhelm their opponents in battle either by attacking or ensnaring them.

When they felt the need to get their hands dirty, Darcy was shown to be a terrifying combatant with their laser scythe. They could spin and swing their scythe to easily push back their opponents and slash them with lethal attacks.

Perhaps the Core's most dangerous and sadistic ability was mind control. For example, it was able to control King Andrias through his crown, forcing him to fight in spite of his emotional breakdown.

In its moon form, the Core had a series of purple thrusters that were used for movement. It also had a port that stored dozens of robotic soldiers for defense.

Weaknesses
Prior to becoming Darcy, the Core was very clumsy and would lose balance and falling over.

As Darcy, the Core could be momentarily disabled by serving its connection to a power source.

History
The Core was created long ago from an amalgamation of the smartest minds from across Amphibia's history. The Core lived under Newtopia Castle in a secret basement in wait until the day when the Calamity Box was returned to Amphibia, while acting as the hidden power behind the Newtopia crown during this time.

After years in dormancy, the Calamity Box finally presented itself when prophesized warriors destined to end the Core arrived in Amphibia. Upon this discovery, the Core sought to reclaim the Box and undo the prophecy by having its conscience transported to Marcy Wu's body through a helmet, leaving the deactivated mechanical body behind and creating a new identity, Darcy.

With one of the warriors as its host, the Core regained control of Newtopia and launched an invasion campaign on Earth as it planned to a millennium ago. During the invasion, Marcy was freed from the Core's control after Sasha Waybright used her sword to sever the cord connected to Darcy's helmet. However, the Core managed to survive inside the helmet and escaped.

After making its escape, the Core ended up initiating its final gambit by connecting to Amphibia's moon and setting a collision course with said planet. Though the Calamity Trio used their powers to destroy the Core's drones, it was not enough to stop it, with Anne Boonchuy ending up absorbing Sasha and Marcy's gems to shoot a powerful blast that destroyed the moon and the Core, ending its reign of terror for good.

Appearances

 * Amphibia
 * s02e14, "The First Temple" (2021)
 * s03e13, "Olivia and Yunan" (2021)
 * s03e16, "Froggy Little Christmas" (2021)
 * s03e25, "The Core and The King" (2022)
 * s03e29, "The Beginning of the End" (2022)
 * s03e30, "All In" (2022)
 * s03e31, "The Hardest Thing' (2022)