When you take a long rest, you must spend at least six hours in an inactive, motionless state, rather than sleeping. In this state, you appear inert, but it doesn't render you unconscious, and you can see and hear as normal.
Sentry's Rest
Raw data
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"When you take a long rest, you must spend at least six hours in an inactive, motionless state, rather than sleeping. In this state, you appear inert, but it doesn't render you {@condition unconscious}, and you can see and hear as normal."
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