Sleep of the Dreamers

Sleep of the Dreamers enters the Battlefield with 3 dream counters on it.
Whenever a source deals 5 or more damage to you, remove a dream counter from it. This ability triggers only once per turn.
At the beginning of your upkeep, if no dream counters are on Sleep of the Dreamers, exile it, then create The Hollow Knight, a 5/5 black Spirit Construct creature token with indestructible, trample and infect.