Rune of Sanctuary
Here’s your answer from recent similar thread by a developer:
This is an intended effect for the Superior set. For balance reasoning we cannot have 3 sets of 15% boon duration.
“Any lump can hack bad guys to death, but it takes skill
and style to turn them into craters and dust.” -Tonn
Number-crunching for ecto salvages – periodically updated
and style to turn them into craters and dust.” -Tonn
Number-crunching for ecto salvages – periodically updated