In LOD, the drops for the 6 Lower Kurast Super Chests weren’t as random as the drops from monsters. There were 65536 drop patterns and whenever a super chest is opened, one of the 65536 patterns was rolled.
Out of the 65536 patterns, 3 patterns contain Ber rune and 11 patterns contain Sur rune. This is only in player setting 7 and 8. So opening a single super chest in player 7 LK has 14 / 65536 chance to drop Sur or Ber or roughly 0.021% chance. Since a good LK map has 6 Super Chests, the odds of getting Sur or Ber per LK run is 0.128%.
This means that if you do 800 LK runs in player 7/8 Single Player, you have a pretty good odds to get a Ber or Sur rune. With how quick a single LK is, it’s probably the best way to farm HRs in Single Player.
If you consider the rates for other runes, not as high as Sur or Ber, but useful regardless, this is the data I found for LOD.
Player Settings 7/8
(30) Ber 3
(29) Sur 11
(28) Lo 2
(27) Ohm 5
(26) Vex 6
(25) Gul 11
(24) Ist 7
(23) Mal 15
(22) Um 10
(21) Pul 14
TOTAL: 84
Oddly enough, Sur has one of the highest chance at 11/65536, which is better odds than some lower runes like Um, Ist, or Vex.
Strangely, Lo has the lowest odds, even lower than Ber at only 2/65536.
I have run Single Player LK at Player 7 for the past 9 days and I think? the same patterns still exist in D2R but my sample size is of course too small.
These are my drops so far in the past 9 days.
3 Surs
1 Ohm
1 Lo
2 Um
2 Gul
3 Pul
1 Mal
Does anyone here know if someone tested the patterns in d2r? Are they still pretty much the same?