Chronos' Lair was added in V5.0.05 as the fifteenth biome in PickCrafter. It can be unlocked in The Sun using 1x 
Time Key and only if you reached prestige 15 or higher. Upon entering it Chronos will great you either happily (he'll say "Welcome") or angrily ("Who dares to enter my lair?!?!").
After reaching this biome from prestige 15 and onward, and after upgrading the 
Endstone Pickaxe, the player can prestige.
