Nova, Inhaler of Sound

When Nova, Inhaler of Sound enters the battlefield, put {x} +1/+1 counters on him,
where {x} was the amount spent to cast Nova.
As long as Nova, Inhaler of Sound has
at least 2 +1/+1 counters on him,
he gains Eavesdrop.
Eavesdrop:
(As long as a creature you control has Eavesdrop,
you can see any opponents hand at any time)