In Transformers fanfiction, the concept of Primus being the core of Earth and the creator of the Primes is a common theme, often depicting him as a powerful, ancient entity who essentially formed the planet's life force and used it to create the first Transformers, known as the Thirteen Primes, with the intention of protecting the universe from evil forces like his twin, Unicron.

Key points about this concept:

Primus as the Earth's core:

This idea portrays Primus as an immense, living being whose very essence is intertwined with the planet Earth, acting as its central energy source.

Creation of the Primes:

Primus, using his connection to Earth, is said to have molded the first Transformers, the Thirteen Primes, from the planet's materials, imbuing them with his will and the responsibility to maintain balance in the universe.

The Matrix of Leadership:

Often, the Matrix of Leadership is depicted as a physical manifestation of Primus's power, allowing the chosen Prime to access his immense energy and guidance.Fanfiction examples:

Stories exploring the connection:

A story might delve into a Prime discovering their deep connection to Earth through their bond with the Matrix, feeling the planet's pulse and understanding Primus's will.

Primus's guidance:

Fanfictions could portray Primus as a guiding force, appearing to the Primes through visions or dreams, offering advice during times of great peril.

The conflict with Unicron:

Many stories use the classic Primus-Unicron dynamic, where Unicron, as the embodiment of chaos, seeks to consume Earth and destroy Primus's creation, forcing the Primes to defend their home planet.