Shump, Jack of Trades

When Shump, Jack of Trades enters the battlefield, create Shump's Guardian, a legendary artifact creature.
{t}: Choose a card name that hasn't been chosen
this turn from among: Healing Salve, Brainstorm,
Dark Ritual, Lightning Bolt, or Nature's Claim.
Create a copy of the card with the chosen name.
You may cast the copy. (You still pay its costs.)