Tile of Fire (5e Spell)
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One 5 foot square you can see within range is lit on fire by magical means. Any creature that starts its turn in the square, or passes through it, must make a Dexterity saving or take 1d6 fire damage. For the duration of this spell, you use a bonus action to dismiss and recreate the magical fire up to 20 feet away from where it last was.
At Higher Levels. When you cast this spell using a 3rd level spell slot or higher, you can decide to deal an extra 1d6 fire damage or create a separate tile of fire (which has separate damage statistics from the original).