Kiera, Head Reaper

When Kiera, Head Reaper enters the battlefield,
you may put a +1/+1 counter on each of up to
three Reaper creatures you control.
Reapers you control with +1/+1 counters on
them have Persist.
{3}{w}{u}{b}: Return Kiera and target Reaper
creature card in your graveyard to the battlefield.