Nightmare Cave Achievements Here is the full list of all 20 Nightmare Cave achievements.Filter Achievement View View Image viewList view Sort by TrueSteamAchievement desc TrueSteamAchievement asc Achievement name desc Achievement name asc TSA Ratio desc TSA Ratio asc Gamers desc Gamers asc Steam order Date won desc Date won asc What are achievement flags? Click to find outApply Shadow Nightmare LordShadow Nightmare Lord defeated Archer Nightmare LordArcher Nightmare Lord defeated Tentacle Nightmare LordTentacle Nightmare Lord defeated The Council Nightmare LordsThe Council Nightmare Lords defeated Summoner Nightmare LordSummoner Nightmare Lord defeated Spirit Nightmare OverlordSpirit Nightmare Overlord defeated Slime LordSlime Lord defeated Guardian Nightmare LordGuardian Nightmare Lord defeated The One RingGive the One Ring to it's rightful owner The CrystalThe Crystal found! The Blue ChestThe Blue Chest opened! Loot CrateCrate of loot opened! Secret CaveSecret Cave found! Secret GemSecret Gem found! Me and the boysMe and the boys are back together! Maximum LevelMaximum level reached! Runic Power!All runes collected! Sword MasterMaximum sword damage reached! Bow MasterMaximum bow damage reached! End of the NightmareNightmare cleared!