Robo leads the pack as they plunge into the Geno Dome in 2300 AD, fighting robotic sentries on a massive conveyor belt
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Geno Dome, 2300 AD

- You have a string of optional quests to undertake now, and as far as combat strength goes the Geno Dome of 2300 AD is near the top. Put Robo in your party and fly to the Geno Dome. You’ll find it in the southeast corner of the map, on a small, remote island.

- Once inside, assuming you have Robo leading your party, you can jump onto a conveyor belt that will subject you to a series of battles against robots, namely Deverminator EXes and Version 4.0s. These things are fabulously weak against Lightning attacks, and Lightning II / Luminaire should be able to wreck crowds of them with little problem. This conveyor belt is a fantastic place to grind levels and TP quickly for the rest of the game, though once you beat this area it will close down permanently.

- Head right in the next corridor. There’s a chute in the far right which you can use to return to the entrance. Use it if necessary; otherwise, head north and into the first door you see. There are three Version 4.0s inside that will attack if you try to take the Elixir or the Lapis from the chests on the right side of the room.

Robo solves a switch-based puzzle in 2300 AD's Geno Dome, home of advanced robotics

- Head back into the corridor and hop on the conveyor belt to your left. Run north, hop off on your left, and hit the switch beside the door. This will open a niche. It’s no use just yet, but you’ll want it open soon.

- Return to the entrance of this area. Take out the Deverminators on the far left, then take the northern corridor. The Version 4.0s ahead go next. Check their room for a Hi-Potion, then go through the door on the left. There are four Laser Guards straight ahead. Easy peasy. Beyond are three switches; hit the left and right switches to open a niche in the previous room, beside a locked door.

- Head back to the room where you just mauled some Version 4.0s. If you stand Robo in the niche beside the large computer he’ll accrue, and carry, an electrical charge. You can use this charge to pop open locked doors by getting Robo into niches before the electricity dissipates. Using this charge you can open a door near the entrance, inside which you’ll find a Hi-Potion and 50,000 gil

- … the door beside the switch-locked niche, which will allow you to grab a Poyozo Doll

- … and the door beyond the conveyor belt in the north. You can’t get to this last one yet, however.

- Head back to the entrance and go through the door near the chute. It leads to an elevator. At the top you’ll find a save point. Beside it is a door. Go through and down the corridor beyond (inside which you can find a Strength Capsule, near the south entrance) to find another door, this protected by two Version 4.0s and two Laser Guards. Beyond the door is an elevator that will take you back to the previous level.

- Two Laser Guards sit to the south. Take ‘em out, then walk west of the door and through the wall decorated with a green arrow. Beyond is a switch that will change the direction of the conveyor belt. Head back to the door and go south to reach the conveyor belt.

- Run to the pod that supplies an electric charge and sit in it for a moment, then rush around the room, up the conveyor belt, and into the niche beside the door on the left. You should have just enough time to open the door. Beyond are two chests containing a Turbo Ether and a Hi-Ether

- … as well as a robot that’s curiously sedate. Touch it and it will follow you around. Lead it south and to the southwest corner of the area. Here you’ll find a second robot guarding another Poyozo Doll. Make the two robots meet and you can slip through to grab the Doll. Also here is a chest containing a Vigilant’s Hat.

- Take one of the elevators upstairs. They’ll take you to a central room near a save point. Save, take out the Laser Guards nearby, check the chest near the save point for a Lapis, and make your way west. A boss waits if you have both Poyozo Dolls.

Robo takes on Atropos XR, his former paramour, while plunging through Geno Dome in 2300 AD

Atropos XR

Robo will have to face Atropos XR alone, but it’s not that difficult a fight. The femme fatale robot uses Robo’s same moves, though her versions do a lot less damage. Use Cure Beam to keep Robo strong, then bring out some strong-but-not-too-strong moves to eat up Atropos’ HP. Robo Tackle is ideal, as it won’t eat through his MP too quickly and rob you of healing. Smack away and Atropos will crumble quickly enough. 

Besting Atropos will permanently raise Robo’s speed by three and his magic defines by 10. Sadly, heart damage will linger forever.

- Once Atropos is gone, approach the switch on the wall near the battle site to open the back room and find a Megaelixir, then run back and save your game. Head west from here and down the stairs before the large, guarded bridge. Along a nearby catwalk you’ll find a chest containing 15,000 gil, and in a rear room… a gruesome spectacle. Check through the right door to find a Hi-Ether.

- Return to the main path and head north. Destroy the Laser Guards on the path… a lot of Laser Guards… then place the Poyozo Dolls you found earlier on the two green lights to the right and left of the large security door at the end of the path. Save and tromp north. A cut scene and a battle await.

Robo leads his comrades in battling Mother Brain, one of the great powers of 2300 AD

Mother Brain

Robo’s mama is a tricksy fighter. She begins the fight as a relatively tame opponent, using some simple attacks and status ailments to bother you. Little trouble, really - except that the displays surrounding her, three in all, constantly provide Mother Brain with healing energy. Unless your damage output is ridiculous, these will constantly undo your hard work. Unfortunately, destroying them will put Mother Brain on the rampage, ramping up her destructive attacks. You aren’t likely to survive an unaided Mother Brain.

The solution? Don’t destroy all of the displays. Take out two of the three, leaving one untouched. This display will continue to heal Mother Brain, but she won’t be able to keep up with your damage output. That done, pummel her with single-hitting Dual and Triple Techs until she falls. Do not use any all-hitting attacks, or you’ll wipe out the last display and put Mother Brain into her frenzied mode. A lengthy fight, but hardly impossible.

Beating Mother Brain will earn you the Teraton Arm and the Crisis Arm. It will also lock the Geno Dome for good and bring this side quest to an end.