Lucky Star (5e Spell)
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You summon a star of energy that explodes on an enemy, dealing incredibly random damage.
Make a ranged spell attack roll against an enemy within range. On a hit, they take 1d20 + your spellcasting ability modifier modifier any damage. You land a critical hit on an attack roll of 19 or 20 with this spell. When a spell slot of 5th level or higher is used, you land a critical hit on a roll of 18 to 20 with this spell. When a spell slot of 9th level is used, you land a critical hit on a roll of 17 to 20 with this spell.
At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, it deals an extra 1d20 damage for every two spell slots above 1st: 2d20 (3rd), 3d20 (5th), 4d20 (7th) and 5d20 (9th).