Diablo 4 features 8 Uber Uniques. However, luck plays a key role, as seen with Reddit user SirBrothers, who, despite farming 40 items, didn’t find the Grandfather.
It’s hard to imagine the number of Uber Duriels needed to yield 40 Uber Uniques, considering the estimated drop chance is around 4% right now with drop rates doubled. Yet, one player’s relentless effort to farm 
The Grandfather has, unfortunately, been fruitless so far, as illustrated below.
Over 40 uniques, 0 Grandfathers
byu/SirBrothers indiablo4
Nevertheless, the player remains undeterred, finding enjoyment in the challenge. How about you? Have you managed to collect all Uber Uniques? Share your experiences in the comments!