Minecraft wiki entry for Firework_Rocket, associated text: Once launched, fireworks fly out vertically, with random horizontal offset up to 5 blocks. In Bedrock and Java editions, fireworks can fly in any of the 6 directions a dispenser can point. After some time, the firework explodes into a colorful explosion based on the effects of the firework stars added upon crafting, or no explosion if no firework star was used. If multiple firework stars were added to the rocket upon crafting, they all explode simultaneously.