The Nemesis Challenge is an unlockable challenge on Cave Story+ and the Nintendo 3DS eShop version. The player starts with a level 1 Nemesis, 10 HP and the Booster v0.8. The challenge takes place at the Underside, which uses the same background as the Outer Wall. Enemies such as Fuzz, Fuzz Cores, Hoppy , Buyobuyo Bases , Buyobuyos , Sandcrocs, Fire Whirls, Night Ghosts, Bats and Orangebells are encountered, along with numerous paths with spikes. The Booster v2.0 is eventually obtained.
|Main||Cave Story • Curly Story|
|Challenges||Machine Gun Challenge • Boss Attack • Wind Fortress • Nemesis Challenge|