From Sonic Retro

Sonic Retro emblem.svg Sonic the Hedgehog 3
Game: Sonic the Hedgehog 3
Level: Marble Garden Zone (mini-boss)
Hits to defeat: 6

The TunnelbotMedia:Sonic3 MD US manual.pdf[1], called Gakin (ガキーン) in the Japanese strategy guide, is the third mini-boss of Sonic the Hedgehog 3, fought at the end of Marble Garden Zone Act 1. The mini-boss is encountered at various points throughout the Act to burrow into the terrain and cause earthquakes.


The Tunnelbot is one of the easiest sub-bosses in the game, made easier by a Shield, which deflects the falling stalactites. Just like Sonic 2's Drill Eggman II, this mini-boss burrows through the ceiling and back. While the mini-boss is burrowing through the ceiling, harmful stalactites will fall. The player should hit the mini-boss whenever it is exposed.

When fighting the mini-boss as Knuckles, the mini-boss will not reach the ground, making it all the more harder for Knuckles to reach due to his lower jump heigh. However, there is a rotating spiked platform that the player can stand on to compensate for this.


When playing as Sonic and Tails together in Sonic 3 alone, Sonic can stay at the very left of the boss arena while the second player defeats the boss using Tails. If Sonic is outside of the Act 2 level boundary when Act 2 starts, the game will crash. Sonic the Hedgehog 3 & Knuckles fixes this by forcing the camera, and Sonic with it, to scroll into the overlap between the Acts.


Sonic the Hedgehog 3
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