ORCA

Description
The Orca was constructed as a secret project in or shortly before 3091. Its development occurred under such total secrecy, that even "an unfortunate delivery driver who slipped through security due to a lapse [and] was caught filming a livefire test with his personal device" was only released from custody 5 years later.

The prototype was created haphazardly, and thus includes some intrinsic flaws like the very difficult control. With suboptimal production standards, it was decided to mothball all prototypes in still-classified locations. While considered a failure, the multiple lessons learned from the Orcas development ultimately resulted in the successful creation of the Poseidon, the Republic's first production superheavy BattleMech, decades later