Singer of the Dark Realm

Singer of the Dark Realm enters play with two
Umbra counters on it.
Singer of the Dark Realm's power is equal to the
number of Swamps you control.
Remove an Umbra counter you control {t}:
Target creature gets -X/-X until end of turn,
where X is the number of Swamps you control.
If you hear a song near the bogs, flee both. -Common
wisdom.