| Sector 2, ID code TRO, is an area of the BSL Research Station from Metroid Fusion. It is reserved for tropical environments and species that thrive in humid climates. Despite the initial map shown from the Navigation Room, TRO is one of the largest areas in the game and the majority of it must be mapped by exploration. The highlights of this sector include enemies that go through life cycles and an overgrown plant that eventually cuts power to the entire station by choking the main reactor with vines. |
Samus also runs into the SA-X for the first time while exploring the sector.
TRO undergoes a number of changes throughout the game. For the most part, it's jungle-like with vines overtaking everything in the area, even machines in the background. Because it's so big, it has a lot of vertical areas to connect to the numerous hidden rooms. The first visit to TRO features numerous caterpillar enemies that crawl along floors, walls, and ceilings alike. After beating the boss Zazabi
and gaining the Hi Jump / Jump Ball ability, the caterpillars will enter a hardened cocoon blocking off certain areas and at the same time, making navigation easier in vertical areas.
The return to TRO becomes necessary when a plant suddenly overtakes the area and chokes the main reactor of the station, cutting power everywhere. By now the catepillar cocoons have become bug-like Ki Hunters with wings and stingers that can do heavy damage to Samus. The source of the out-of-control plant is the boss Nettori
, a strange statue infected by X Parasites. Defeating it will restore power, return TRO to normal, and give Samus the Plasma Beam ability.