Stretching Room

Whenever a Spirit or Human Creature enters the battlefield under your control, put a Stretch
counter on Stretching Room
{3}{t} Sacrifice Stretching Room - target creature
gets a +1/+1 counter for each Stretch Counter
on Stretching Room, then return four target
artifact or spirit creatures from your graveyard to
your hand.
Is this haunted room actually stretching? Or is it your imagination?