Mana Error: I Spam Level 1 Spells Until They Become Catastrophes

Everyone knows the rules of magic: Powerful spells cost mana. Run out of mana, and you're dead. When I awakened in this world, the System told me I had the lowest mana capacity in history: 10 MP. Everyone laughed. They called me a dud. They said I’d never cast anything stronger than a candle flame. They were wrong. They didn't see my passive skill: [Mana Regeneration: ∞/sec]. I can't cast the Grand Meteor spell. But I can cast "Small Fireball" ten thousand times in a minute. Let's see which one kills the Dragon faster.