I read this four volume series this spring while sheltering at home, and on many levels I would recommend this series because the storyline spans both the every day world as well as this fantasy world, Ahoratos. Each book feature children and youth who are developing into Prince warriors as they undertake a series of missions with the guidance of a mysterious being, Ru'ach and the wisdom of the Source, which sends them empowering messages in the cave of revelation as well as through a mystical app on their cell phones.
However, on another level, the battles on Ahoratos (which is Greek for "Unseen") prepares the warriors for earthly challenges and interpersonal struggles in school, at home and in the community. The key truths that guide their fight against evil actually are based on the spiritual warfare text in Ephesians 6 and other passages from the Bible -- although the source of these quotations are not made explicit in the story.
The authors, Priscilla Shirer and Gina Detwiler have truly mastered the art of cliff hangers, ending each chapter with a page turning hook to keep you reading. Also the authors put a lot of effort into developing the character of the warriors, tracing their strengths and weaknesses, their growth and failures, with realistic reactions, impulses and dialogue. The villains are more uni-dimensional, but the struggles and temptations portrayed are deftly described.
My favorite in the series is Book II, The Unseen Invasion, which details the power of faith, and the struggle for truth and obedience, plus the challenge of taking our thoughts captive to God:
2 Corinthians 10:5
We demolish arguments and every pretension that sets itself up against the knowledge of God, and we take captive every thought to make it obedient to Christ.
This is a worthwhile series and a great read-aloud because of the lively action, descriptions, and cliff hangers. However, sometimes the action upstages the character development especially in Books III and IV. Overall though, I would recommend these books -- especially the second volume.