The latest Diablo 4 patch adds a new Uber Unique to the game called Ahavarion, Spear of Lycander for players to chase. The item isn’t exactly new because it was already present in Diablo 3, but had a different, yet very similar effect:
The shrine theme continues in Diablo 4, where Ahavarion Spear of Lycander is an extremely rare drop and the effect makes your character gain a random Shrine effect for 10-20 seconds after killing an Elite enemy. Can only occur once every 30 seconds.
For more information about Patch 1.1, you can check out the official patch notes.