Rocket

A rocket (ロケット) is a vehicle used to obtain thrust from a rocket engine by pushing the rocket forwards simply by throwing their exhaust backwards extremely fast. When Mega Man Volnutt was stuck in Elysium in the end of Mega Man Legends 2, Roll Caskett and Tron Bonne teamed up to create a rocket to rescue him, but their initial attempts didn't work. Teisel Bonne mentions that the rocket shown in the ending was the tenth rocket they built, and it exploded while flying.

Mega Man Legends 3
In Mega Man Legends 3, the 28th rocket was under development in Klickelan Island, and Roll had a Rocket R&D Lab. The game's official site had a "Rocket Development Progress" section that represented the game's completion, with images of the rocket's development and three Servbots talking. It had six entries between November 16, 2010 and April 19, 2011 before the game's cancellation in July 18, 2011. In the 25% completion update, Servbot #33 says that the 27th rocket launched straight into the city.