Gods' Games We Play, Vol. 1 (light novel) — Kei Sazane

In their (overabundance of) free time, the gods grew bored and decided to create challenging battles of wits to spice things up! Their opponent? Humanity! A select few players called “apostles” meet the gods on the spiritual realm's playing field to beat the deities at their own games. A former god named Leshea has woken after sleeping for thousands of years, and her first demand is to meet “this era's very best player!” She is introduced to Fay, an acclaimed rookie apostle. Together, they plan to challenge the gods and win the ultimate prize, but no one in human history has managed to clear ten games -- because the gods can be capricious, outrageous, and sometimes downright incomprehensible! In the face of absurdity, what can the apostles do but enjoy the contest to its fullest?