Diablo III: Reaper of Souls will introduce a new end-game feature named Nephalem Trials. These special portals will open to offer really cool challenge-based encounters.

These Nephalem Trials spawn randomly in the world.

Some of these challenges include waves and waves of monsters. The quickly you deal with them get rewarded with a number of resplendant chests.

There are many things yet to be announced about Diablo III: Reaper of Souls at BlizzCon — according to Josh Mosqueira. The size of ACT V is comparable in size to ACT II.

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