Dark Beam (5e Spell)
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A dark purple and black beam of dark magic 30 feet long and 5 feet wide streaks from you in a direction of your choosing. Each creature in the line must make a Constitution saving throw. A creature takes 2d10 dark damage and gains 1 level of exhaustion on a failed save. A creature can only gain a maximum of one level of exhaustion from this spell.
At Higher Levels. When you cast this spell using a spell slot of 3 or higher, the damage increases by 1d10 for each spell slot above 2nd.