Delve too Deep

Delve is a static ability that functions while the spell with delve is on the stack. “Delve” means “For each generic mana in this spell’s total cost, you may exile a card from your graveyard rather than pay that mana.”

The delve ability isn’t an additional or alternative cost and applies only after the total cost of the spell with delve is determined.

Multiple instances of delve on the same spell are redundant.