Memories of Joy

As Memories of Joy enters the battlefield, put X
joy counters on it.
{t}: Target opponent who does not control a
creature named Joyful Tree creates a 0/2 Joyful
Tree creature token with "This creature is every
color." and "This creature cannot attack." Then
each opponent who controls a Joyful Tree gains
X life, where X is the number of joy counters on Memories of Joy. You gain life equal to the total
life gained this way.