Storm Mage's Mastery

Whenever you copy an instant or sorcery spell
one or more times, choose one—
• Draw a card.
• Storm Mage's Mastery deals 3 damage to any
target.
{1}, Discard a card: The next instant or sorcery
spell you cast this turn gains Storm. Activate only
once each turn.(When you cast it, copy it for each
spell cast before it this turn.)