Hyper Eggrobo (ハイパーエッグロボ) is the eighth boss of Sonic Advance 3, and is the regular final boss of the game unless the player collects all 7 Chaos Emeralds and the leader is Sonic.
Dr. Eggman will use the Hyper Eggrobo's two massive hands to attempt to squash the player. As he does so, he also takes out two of the four platforms the player has to stand on, though they'll eventually reappear. At this point, the player can stand on the back of the rising hands to attack Eggman. Afterwards, Eggman will bring the hands to the side and begin creating red spheres from the blue sphere just above the emerald. These spheres can hurt the player and and will also push them back into the hands. However, they can also be stood on, allowing the player to again attack Eggman. The hands will play "Pong" in a sense, keeping the spheres bouncing back and forth. Eggman will also use the hands to punch and smash the player, signified by the hands either balling up and spinning in the background, or by going to both sides of the screen and moving up and done in an attempt to home in. Gemerl is just above Eggman. When you finish the fight, either of below could happen, depending on if the player has all 7 Chaos Emeralds or not, and if the leader is Sonic or not:
- 6 or less Emeralds/Have all 7 Emeralds, but leader not Sonic: Both Eggman and Gemerl run away, but the lead character hit Eggman's Eggmobile, Gemerl jumps off the edge, and the game ends with the Master Emerald restoring the shattered world.
- 7 Emeralds with leader Sonic: Both Eggman and Gemerl run away, but Gemerl jumps off Eggman's Eggmobile, steals Sonic's Chaos Emeralds, and becomes his super form. He runs off, but Sonic uses the power of the Chaos Emeralds, and becomes Super Sonic. Eggman & Sonic team up, and the true final boss starts.