Nephalem rift

Nephalem Rift (previously called "Loot Run") is a randomized dungeon system for Diablo III, introduced in Reaper of Souls. The rift runs last 10-20 minutes and consist of random areas, monsters, and bosses. The layouts stem from taking the tilesets and dungeons of the game and re-organizing/shuffling them. Monsters are likewise re-shuffled, found in combinations otherwise not present. The rifts have 1-10 levels. Each level is effectively a different dungeon, with a different monster combination. They are accessed via Nephalem Obelisks.

During the event, a progress bar will appear just beneath the game's mini-map, starting at 0%. As the player kills monsters, the bar increases. Once it reaches 100%, the event's Rift Guardian will spawn near the player.

Buffs are present in the rifts that are otherwise not present, such as one-shot abilities, no cast cooldown or vulnerability, etc.

Adventure Bosses
Completion of the rift originally rewarded the player a Greater Horadric Cache.

Voracity is one of the creatures that spawns

Stonesinger is one of the creatures that spawns