Heroes of the Last Dungeon - Hiro & Olly, #1

Legends, the adventurers of a world filled with wonders, thrill seekers chasing the most dangerous beasts, searchers of the rarest treasures, and traders in folklore and myths. For the poverty-stricken Metropolis of Teigen, this mysterious occupation and its yearly test is the only hope citizens have in changing their station in life. However, for the young wide-eyed Hiro and the clever Olly, the word 'Legend' is the matter of a childhood dream coming true.
Sneaking their way into the testing center, they find themselves amongst the most skilled warriors in the entire metropolis. There, they take on the challenge of surviving a life or death game inside the brick layered confines of the most dangerous and puzzle filled land in the city, the Last Dungeon.