Evan, God of Excess

Whenever you cast a spell, if you spent less mana
to cast it than its converted mana cost, add an
amount of colorless mana equal to the amount
of mana you didn't spend to cast it.
Mana doesn't empty at the end of your steps or
phases.
{x}{1}: Put a +1/+1 counter on target creature.
Creatures you control with +1/+1 counters are indestructible.
"Its just mana, play around it"