Glemn, Kirkyard Guardian

Whenever a creature is put into a graveyard
from a library you may pay {1}. If you do, create a
token that's a copy of that creature, except it is a
1/1 and is a Spirit in addition to its other types.
{4}{t}, Mill {x} cards, where {x} is the number of
tokens you control.
Widow tears keeps graveyard grass green.