Minecraft wiki entry for Crossbow, associated text: A shot firework rocket explodes instantly when it hits a mob or block.‌[Java Edition only] If the firework rocket has no explosion effect, it deals no damage. The explosion of a firework rocket deals 5 to 6 points of damage, with one firework star. The explosion has a radius of roughly 4 blocks, which is unaffected by the firework star's effect. Each additional firework star on the rocket deals an additional 1 to 2 points of damage, for a maximum of 11 × 5.5 to 18 × 9 with 7 firework stars. The flight duration of the firework increases the maximum range the firework can travel before exploding, but does not affect the damage output. Likewise, the damage remains the same regardless of any dyes used. The Piercing enchantment causes the firework rocket to pierce a number of entities based on its respective level before exploding.‌[Java Edition only]