Operation Under Book 4

Book 4 ( the final book in the series)starts with an alpine mission that leads into others. The second half of the book follows the life of Sker (Operation Under’s most prolific troglodyte). Each book is signed and comes with an aged pouch containing a piece of tunnel concrete. The book is designed by Eduardo from Superchief and Mike Meds.
This book marks the end of phase 1. Sales will help fund phase 2 .