Although this article is based on official information, the actual name of the article's subject is pure conjecture.
This article's name is conjectural.
Tunnelbot is a robot built by  Dr. Robotnik, that appears at Lava Reef Zone in and Sonic & Knuckles . The robot serves as an minor obstacle during the gameplay, as it seems to be a larger variation of the first Sonic Mania Tunnelbot seen in Marble Garden Zone with four drill attachments.
Sonic & Knuckles
Knuckles encountering the Tunnelbot in Lava Reef Zone Act 1.
and its add-on game Sonic & Knuckles , the Tunnelbot appears three times in Sonic the Hedgehog 3 & Knuckles Lava Reef Zone Act 1, once in Sonic's story and twice in Knuckles' story (depending on if the player takes the upper pathway behind the robot). In both stories, when the player faces it in the open area, the robot is about to start the drilling process, which makes the ground below collapse. The player can hit it with a Spin Attack an arbitrary number of times but cannot be defeated this way.
In Sonic's story, the robot falls into the lava pool, and in Knuckles' story, it attempts the same process but stays on the edge of the upper platform where it remains intact.
, Tunnelbots appear again in Sonic Mania Lava Reef Zone Act 1. Once again, the player can land numerous hits on it, but the Tunnelbot cannot be defeated by regular means.
In gameplay, the player faces off with the Tunnelbot in the iron fence area. Once again by drilling at one place, the drone causes the floor to crumble, while falling down to the lava pool. Midway through Act 1, one Tunnelbot is seen causing the lava pool to raise, as the player has to escape it, while the Tunnelbot once again falls down to the pit.
The boss of Lava Reef Zone Act 1,
Drillerdroid, is an advanced model of the regular Tunnelbot with a heavily-armed head drone and bulkier parts around its drill attachments.
If the player manages to pass through the Tunnelbot safely, the player can usually find an item or something else from the other side. In , an Sonic & Knuckles extra life ( Sonic) or alternative pathway ( Knuckles) can be found.
Main articles ( Sonic 3, Sonic & Knuckles, Sonic 3 & Knuckles) | Gallery ( Sonic 3, Sonic & Knuckles) | Beta elements | Staff ( Sonic 3, Sonic & Knuckles)
Sonic ( Super Sonic, Hyper Sonic) | Tails ( Super Tails) | Knuckles ( Super Knuckles, Hyper Knuckles) | Dr. Robotnik | Mecha Sonic ( Mecha Sonic's Super State) | Animals ( Flicky ( Flicky's Super State), Pocky, Pecky, Cucky, Ricky, Rocky)
Batbot | Blaster | Blastoid (Carnival Night Zone) | Blastoid (Hydrocity Zone) | Bloominator | Bubbles | Bugernaut | Butterdroid | Catakiller, Jr. | Chainspike | Clamer | Cluckoid | Corkey | Dragonfly | EggRobo | Fireworm | Flybot767 | Hyudoro | Iwamodoki | Jawz | Madmole | Mantis | Mega Chopper | Monkey Dude | Mushmeanie | Orbinaut | Penguinator | Pointdexter | RhinoBot | Ribot | Rock'n | Sandworm | Skorp | Snale Blaster | Spikebonker | Spiker | Star Pointer | TechnoSqueek | Toxomister | Turbo Spiker
Angel Island Zone | Hydrocity Zone | Marble Garden Zone | Carnival Night Zone | IceCap Zone | Launch Base Zone | Special Stages | Bonus Stages
Sonic & Knuckles
Mushroom Hill Zone | Flying Battery Zone | Sandopolis Zone | Lava Reef Zone | Hidden Palace Zone | Sky Sanctuary Zone | Death Egg Zone | The Doomsday Zone | Special Stages | Bonus Stages
Azure Lake Zone | Balloon Park Zone | Chrome Gadget Zone | Desert Palace Zone | Endless Mine Zone
Doctor Robotnik’s Flame Craft | Doctor Robotnik’s Whirlpool Machine | Tunnelbot | Self D-Struct Machine | Iceball | Swing’m Spikez | Hei Hou | Gapsule | Barrier Eggman | Guardian | Heat Arms | Egg Mobile-H | Flying Eggman | Red Eye | Death Ball
Doctor Robotnik’s Flame Craft | Doctor Robotnik’s Waterspout and Depth Charge Machine | Doctor Robotnik’s Jet Drill Pod | Doctor Robotnik’s Energy Ship | Doctor Robotnik’s Freeze-O-Matic | Ball Shooter | Beam Rocket | Big Arm | Jet Mobile | Hang Mobile | Egg Golem | Hot Mobile | Knuckles | Mecha Sonic | Mecha Sonic's Super State | Great Eggman Robo | The Doomsday Zone
Bound Jump | Double Jump | Fireball Spin Dash | Glide | Gliding Knuckles Attack | Hyper Flash | Insta-Shield | Propeller Flying | Spin Jump | Spin Dash | Spin Attack | Wall Climb
Air Bubbles | Balloon | Banana | Bomb | Booster | Bumper | Bumper wall | Cannon | Capsule | Change | Chaos Emerald | Cloud | Continue | Fan | Jump Stand | Monitor ( Water Shield, Flame Shield, Invincibility, Lightning Shield, Super Ring, Power Sneakers, Extra Life, S, Eggman) | Movable box | Mushroom | Pulley | Ring | Signpost | Self-Propelled Bomb | Slow-Down Shoes | Snowboard | Sphere | Spikes | Spring | Spinning Top | Star Post ( Star Circle) | Super Emerald | Switch | Transport | Vine | Zip Line
Angel Island | Barrel | Blue Knuckles | Conveyor Belt | Corkscrew loop | Crusher | Debug Mode | Fireball Cannon | Flipper | Flywheel | Freeze | Giant spear | Goal | Gravity Control Switch | Gumball | High-speed elevator | High-speed warp tube | Icicle | Jewel Radar | Perfect Bonus | Platform-raising Wheel | Pole Elevator | Relief | Reverse | Ring Shooter | Seesaw | Shuttle loop | Slot Machine | Snowblower | Sonic & Knuckles • Sonic the Hedgehog 3 | Spiked ball | Strange Relief | Time Attack | Tornado | Tunnelbot | Warp Point | Winding Tunnel | Wonderman
Main article | Gallery | Beta elements | Staff
Sonic the Hedgehog ( Super Sonic) | Miles "Tails" Prower ( Super Tails) | Knuckles the Echidna ( Super Knuckles)
Dr. Eggman | Hard Boiled Heavies ( Heavy King, Heavy Gunner, Heavy Shinobi, Heavy Magician, Heavy Rider) | Phantom Heavies ( Phantom King, Phantom Gunner, Phantom Shinobi, Phantom Magician, Phantom Rider) | Animals ( Becky, Cucky, Flicky, Locky, Micky, Pecky, Picky, Pocky, Ricky, Rocky, Tocky, Wocky) | Jimmy
Zones Green Hill Zone | Chemical Plant Zone | Studiopolis Zone | Flying Battery Zone | Press Garden Zone | Stardust Speedway Zone | Hydrocity Zone | Mirage Saloon Zone | Oil Ocean Zone | Lava Reef Zone | Metallic Madness Zone | Titanic Monarch Zone | Egg Reverie Zone | Special Stage | Bonus Stage
Armadiloid | Aquis | Asteron | Ball Hog | Bat Brain | Blaster | Blastoid | Bugernaut | Bumpalo | Buzz Bomber | Cactula | Catakiller, Jr. | Chopper | Clucker | Crabmeat | Dango | Dragonfly | Eggrobo | Fireworm | Flasher mk.II | Gohla | Grabber | Hotaru | IceBomba | Iwamodoki | Jawz | Jellygnite | Juggle Saw | Kabasira | Kanabun | Madmole | Matryoshka-Bom | Mecha-Bu | Mega Chopper | Mic Drop | Moto Bug | Newtron | Octus | Poh-Bee | Pointdexter | RattleKiller | Rexon | Roller mk.II | Scarab | Sentry Bug | Shutterbug | Silver Sonic | Spiny | Splats | TechnoSqueek | Toxomister | Tubinaut | Turbo Spiker | Turbo Turtle | Vultron | Wall Crawl | Woodrow
DD Wrecker | Amoeba Droid | Heavy Gunner | Big Squeeze | Shiversaw | Hotaru Hi-Watt | Dive Eggman | Uber Caterkiller | Meter Droid | Drillerdroid | Egg Pistons mk.II | Crimson Eye
Death Egg Robot | Mean Bean Machine | Weather Globe | Spider Mobile | Heavy Shinobi | Metal Sonic | Laundro-Mobile | Heavy Magician | Mega Octus | Heavy Rider | Heavy King | Gachapandora | Phantom Egg | Phantom King and Klepto Mobile
Bound Jump | Climb | Double Jump | Drop Dash | Fireball Spin Dash | Glide | Insta-Shield | Propeller Flying | Ring Spark Field | Spin Dash | Spin Attack | Spin Jump | Super Peel Out | V. Maximum Overdrive Attack
Gimmicks and obstacles
Beanstalk | Bomb | Breakable Block | Bumper | Bungee Rope | Bumper wall | Capsule | Catapult | Conveyor Belt | Crusher | Dash Panel | Fan | Fireball Cannon | Flipper | Flywheel | Goal Plate | High-speed warp tube | Ice Spring | Platform-raising Wheel | Pulley | Ruby Mist | Seesaw | Size Beam | Snowblower | Spiked ball | Spikes | Spring | Star Post | Switch | Transport | Vine | Zip Line
Air Bubbles | Chaos Emerald | Giant Ring | Giant spear | Klepto Mobile | Little Planet flowers | Master Emerald | Metal Sonic Projector | Medallion | Monitor ( Aqua Shield, Hyper Ring, Eggman Mark, Flame Shield, Invincibility, Player Swap, Power Sneakers, Random, S, Shield, Super Ring, Thunder Shield) | Phantom Ruby | Ring | Robot teleporter | Sphere | Star Circle | Time Warp Plate | UFO | Warp Point
Angel Island | Auto Running | Continue | Debug Mode | Freeze | Level Select | Little Planet | Mega Mack | Perfect Bonus | Shuttle loop | Time Attack | Time Over | Tornado | Tunnelbot | Winding Tunnel