Expel the Unworthy

To determine a spell's total cost, start with the mana cost (or an alternative cost if another card's effect allows you to pay one instead), add any cost increases (such as kicker), then apply any cost reductions. The spell's mana value remains unchanged, no matter what the total cost to cast it was.

The kicker ability doesn't let you pay a kicker cost more than once.

Use the creature's mana value as it last existed on the battlefield to determine how much life its controller gains.