Glen, Sailor of Time

Cast Glen, Sailor of Time with x mana, where x is
the amount of happy memories played this turn.
When Glen, Sailor of Time enters the battlefield, destroy all cards with 'Sadness' an opponent
controls.
First strike
Double strike
Lifelink
"He is the one who sails on the sea of time and
brings joy to those in need, closely followed by his Rovermore angel