Drowner of hope rules

{5}{u} create four 1/1 colorless Eldrazi Scion
creature tokens. They have
“Sacrifice this creature": Add {c}
Drowner of hope can not be destroyed
unless its anchor is if its toughness reaches
zero then it is exiled for two turns
it then returns with +5/+5 added
on to it
as it is a boss it has 5/20