Niv-Mizzet, le Cérébropyre

If a spell or ability causes you to draw multiple cards, Niv-Mizzet's ability triggers that many times.

If dealing 1 damage to a permanent or player causes you to draw a card, perhaps because Niv-Mizzet is enchanted by Curiosity, you'll continue this loop until the loop is interrupted, perhaps by a player losing the game.