Light Sleeper (5e Feat)
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On each short rest, you can recover additional Hit Points equal to +25% of all Hit Dice used (minimum of 1) without expending a Hit Die.
On each long rest, you regain spent Hit Dice equal to 75% of your total Hit Dice. You also gain the benefits of a long rest during which you sleep or performs light activity: reading, talking, eating, or standing watch for no more than 4 hours, instead of 2.