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 a target within range. On a hit, they take force damage equal to 1d20 plus your spellcasting modifier.
You land a critical hit on an attack roll of 20 with this spell, rolling twice as many damage dice.
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). In addition, its critical damage effect triggers on a roll of 19-20 using a spell slot of 2nd level or higher, a roll of 18-20 when using a spell slot of 4th level or higher, and a roll 17-20 when using a spell slot of 8th level or higher.