Retrogression Keeper

Retrogression Keeper is a two-book isekai series by Jonathan Brooks, author of Magical Fusion, Earthen Contenders, and Dungeon World. The series follows Bax, an ordinary human from Earth who finds himself suddenly transported to an organisation spanning multiple powerful races across the universe. His confusion only deepens when he learns the horrifying truth: Earth is being forcefully inducted into something called the Retrogression System, which will introduce monsters to the planet whilst simultaneously eliminating all human technology.

The Retrogression System represents a fundamental transformation of Earth's reality. Humanity will lose access to modern technology and must adapt to a world where survival depends on personal power, magical abilities, and the capacity to fight monsters. It's a terrifying prospect, and there's nothing Bax - or anyone else - can do to prevent it. Instead, Bax discovers he's been enrolled in the Keeper Recruit program, an intensive training initiative designed to create powerful protectors for worlds included in the System.

Bax isn't just being trained as a regular Keeper, however. His role is far more significant: he's to become a Keeper Guide, essentially a teacher for future human Keepers once Earth's Retrogression cycle begins anew. This means Bax must master not only survival and combat but also the pedagogical skills necessary to train others. The responsibility weighs heavily - he'll be responsible for preparing humanity's defenders against threats they can barely imagine.

Unfortunately, Bax's recruitment comes at the worst possible time. He was transported from Earth whilst suffering from the early stages of flu contracted from a co-worker. The experience of being ravaged by the virus in an alien environment proves unpleasant, to say the least, but he eventually recovers with sufficient rest. When Bax finally emerges from his room, ready to properly begin his training as a Keeper Guide, he makes a shocking discovery: the rest of the Cooperative appears to be completely abandoned. Through circumstances beyond his control, Bax has inadvertently eliminated not only the other recruits but all of the teachers as well.

This catastrophic situation leaves Bax facing an impossible question: what is a Keeper Guide recruit supposed to do when there's no one left to teach him? He must somehow educate himself about Keeper abilities, learn to protect entire worlds from monstrous threats, and prepare to train humanity's future defenders - all without guidance, instruction, or even basic support. His journey becomes one of self-discovery and improvisation as he attempts to fulfil responsibilities that require knowledge he doesn't possess.

Jonathan Brooks brings his expertise in LitRPG / GameLit mechanics to this overpowered main character series. The books feature detailed progression fantasy elements with statistics, levelling systems, and the strategic gameplay that fans of Brooks' other work expect. What distinguishes Retrogression Keeper is its focus on a protagonist who must not only become powerful but also understand his abilities well enough to eventually teach others. The series explores themes of responsibility, self-directed learning, and the pressure of knowing that an entire world's survival may depend on your success.

The Retrogression Keeper series currently consists of two books: The Lone Keeper (2025) and The Alternate Keeper (2025). For readers who enjoy portal fantasy, OP MC protagonists, and stories where characters must navigate extraordinary responsibilities without proper preparation, this series offers fresh takes on familiar LitRPG elements.

Books in the Retrogression Keeper Series

Book 1: The Lone Keeper (2025)

Bax's journey begins with confusion and rapidly escalates to catastrophe. Transported from Earth to the Keeper Recruit program, he initially struggles to understand what's happening and why. Learning that Earth faces transformation through the Retrogression System - where monsters will appear and technology will vanish - fills him with understandable panic. His situation worsens when he falls ill from the flu he'd contracted before transportation, forcing him to recover in isolation before properly beginning his training. When Bax finally emerges, ready to learn how to become a Keeper Guide, he discovers the unthinkable: everyone else is gone. Through inadvertent actions he doesn't fully understand, he's eliminated both his fellow recruits and all the instructors. Now completely alone in the Cooperative, Bax must figure out how to teach himself everything required to protect Earth and prepare humanity's future defenders - without guidance, without support, and under immense pressure.

Book 2: The Alternate Keeper (2025)

With Earth transformed and the Retrogression System in effect, Bax now operates in Derelya, the world he's duty-bound to protect. However, he discovers a significant complication: his presence in any location has a detrimental effect on ambient energy if he remains too long. This forces him to stay constantly mobile, never settling in one place. After his original party abandons him, Bax travels solo with twin goals: learning more about the world he must protect and gaining the population's support - despite Keepers being widely despised. During his travels, he encounters another outcast and forms a new partnership. Bax hopes to help his new party member grow stronger and potentially become another Keeper to assist in protecting Derelya from monstrous threats. However, when a Task to defeat a powerful Remnant goes sideways and tragedy strikes, Bax's desperate attempt to fix the situation accidentally triggers something that will change both the world and the entire Retrogression System forever.