Helgrove's Soul Snare

Whenever a creature would be sent to a graveyard, exile it instead and put a soul counter on
Helgrove's Soul Snare.
When Helgrove's Soul Snare leaves the battlefield
put X 1/1 blue spirit creature tokens with Flying
onto the battlefield under your control where X
is equal to the number of soul counters on
Helgrove's Soul Snare
{2}{b}{t}: Return Helgrove's Soul Snare to its
owner's hand