Burning blast

Launch a small sphere of fire (colored red, blue or yellow) from your fingertip at a target. Make a ranged spell attack. On hit, the target bursts into flame the same color as the sphere, dealing damage depending on the color of fire. (red: 1d8 fire damage, blue: 2d6 fire damage, yellow: 2d10 fire damage). The target stays on fire for 2 rounds, taking damage depending on the color of fire each round. (red: 2d6, blue: 1d10, yellow: 1d8).