You create a birdcage of flames around one medium-sized or smaller creature. Any creature within 5 feet of the target must make a DEX saving throw. On a failed save, the creature takes 3d6 fire damage. The damage is halved if the creature succeeds.

As long as the spell persists, any creatures that move 5 feet near the cage on their turn or end their turn within 5 feet of the target must make a DEX save and take 3d6 fire damage if it fails. The damage is halved if the creature succeeds.

If the creature inside the cage tries to physically move through the cage and escape, they must make DEX saving throw or suffer 5d6 fire damage. The damage is halved if the creature succeeds.

At Higher Levels: When you cast this spell using a spell slot of 3rd level or higher, you can target large creatures and all damage values are increased by 1d6 for each slot level above 2nd.