Revan, Prodigal Knight

{u}{t}, Counter target spell.
{b}{t}, deal 1 damage to any target.
{r}{t}, put a +0/+1 counter on target creature.
{g}{t}, regenerate target creature.
If Revan, Prodigal Knight would be removed from the battlefield,
search your deck and replace it with Revan, Vengeful Conqueror.