Boon of Unlimited Death (5e Epic Boon)
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Boon of Unlimited Death
Prerequisite: 20 levels in Death's Incarnate class
It seems that Death does not have a limit, after all.
You can use your Steps between the strings and Omen of Undeath features an unlimited number of times, but you still need to expend a hit die when using Omen of Undeath feature. Additionally, the time needed to pass for your next use of Power Beyond Reason shortens to one full day.