The Beam Rocket (ビームロケット,Bīmu Roketto?) is an Egg Mobile combat module boss that appears in Sonic the Hedgehog 3. It is the second of three bosses fought at the end of Launch Base Zone Act 2 and takes nine hits to be destroyed. The boss battle takes place on a platform suspended below the Death Egg as it gets re-launched. If playing Sonic the Hedgehog 3 and not the full game Sonic the Hedgehog 3 & Knuckles, the Big Arm boss is fought immediately afterwards as the final boss (the boss is removed from Sonic and Tails' playthrough and is instead fought by Knuckles).
The Beam Rocket is created by Dr. Robotnik, and is a tall rocket craft powered by two pairs of rocket engines. It is composed of three parts with a cockpit set on the top. The cockpit is guarded with a sparkling, possibly electric, spiked ball that keeps changing its shape while hovering above it. The above and center parts have two laser beam cannons moving on the sides.
During gameplay, the Beam Rocket will either come down from above or rise up from below on the left or right side of the screen. The weapons visible are the laser cannons that will fire twice each time Dr. Robotnik passes by the screen. The craft is best attacked when it is rising up from below the floor as the only part of it that is vulnerable to attacks is the cockpit. However, the player has to watch out for the morphing spiked ball that orbits above the cockpit.
Unlike other regular bosses, nine hits are required to defeat the Beam Rocket - four hits destroys the top part of the rocket, another four destroys the middle part, and the ninth hit destroys the whole craft.
If the player is playing in Sonic the Hedgehog 3 , the final boss battle takes place directly afterwards. Dr. Robotnik's Egg Mobile will rise up and attach itself to the Big Arm as the sky darkens ominously. In locked-on version, Sonic the Hedgehog 3 & Knuckles, Sonic completes the Launch Base Zone after defeating the Beam Rocket, while the cutscene after shows the score results is the same, except that Sonic and Tails end up in the Mushroom Hill Zone after staying on the platform.
In Knuckles' scenario, Knuckles fights this boss in a different upper section due to the Death Egg being relaunched and destroyed before Knuckles' storyline. EggRobo controls the craft, while the tactics remain unchanged except that the morphing spiked ball can start at a different position for Knuckles, leaving sightly less opportunities to attack. After nine hits, EggRobo will fly up from the destroyed Beam Rocket to take control of the Big Arm.
In Sonic the Hedgehog 3, if the player controls Sonic along with Tails as a partner, Tails does not appear during this boss battle nor in the Big Arm fight, as he was left after the battle of the Ball Shooter. However, he appears alongside Sonic in Sonic the Hedgehog 3 & Knuckles.
In the locked-on version, Launch Base Zone is the only Zone in the game that does not have any Capsule to open after fighting this boss as Sonic or Tails.