SleepThe sleep spell description (PHB, page 276,) says to roll 5d8 startto determine the total HP of creatures that can be affected, starting from the lowest hit points. Undead Undead and creatures immune to charm are not affected by this spell.
Assuming I have a human wizard with 20 health, a zombie rat with 5 health, and a sleepsleep spell roll of 20 hitting both. Does the undead ratsrat's health pool interact with the total sleep damagesleep pool, thus saving the wizard from sleep, or is the word affected"affected" meant to include both the spell is unaffected along with immune subjects?
I already understand the undead rat will not be put to sleep either way. I just wish to be clear if the undead would put a buffer of sleepsleep hp of the wizard or not.
By comparison, the spell color spraycolor spray with similar mechanics goes out of its way to say you ignore targets that already can't see. Where as sleepWhereas sleep only states ignore unconscious.