The main Dynamo is a puzzle element in the Metroid Prime 2: Echoes room Main Gyro Chamber. It consists of an unstable ball of purplish static energy surrounded by two spinning ring-like mechanisms that are also unstable. To disable the rings, Samus must open up security doors leading to other parts of the room and then take an Elevator up to two chambers at the top, where she must destroy objects made of Denzium to summon a Bomb Slot, which, when activated, will summon a Rubiks Puzzle. This puzzle will summon another Bomb Slot, which will deactivate a ring. The first ring becomes a platform for use to get to other chambers faster, while the other has a Spider Ball Track on its interior, allowing Samus to boost off of them so that she can break through glass windows blocking passages to other areas (such as Aerie). As for the core, a final piece of the puzzle lies at the bottom, although it is optional. An Echo Gate must be lowered to reveal a Kinetic Orb Cannon, which will shoot Samus at the core, destroying it and revealing a Power Bomb Expansion.
"Object scan complete. Target is part of the main Dynamo. Unit is unstable. Safeguards offline; this unit needs to be shut down manually."
"Object scan complete. Target is part of the main Dynamo. Unit is offline. Surface is no longer charged."
"Object scan complete. Unit is the main Dynamo core. Unit is unstable. It can't be destroyed with conventional weapons. A tremendous kinetic impact may damage it."
- Donkey Kong Country Returns, the first Retro Studios-developed non-Metroid Prime Trilogy game, contains a reference to the main Dynamo in the level 7-R "Lift-Off Launch". At the beginning of this level a spinning gyroscope very similar to the Main Dynamo can be seen in the background. The core suspiciously resembles a Portal.