Disclaimer: Anyone even CGL can use this as a base for their own version of the scrapheap Challenge. This is not a canon scenario.
I posted a design Challenge thread up with the construction rules for this scenario here
https://bg.battletech.com/forums/index.php/topic,82854.msg1967494.html#new . As you can see the basic premise is that people from around the inner sphere are invited to participate with their own custom primitive/retrotech battlemechs(with some technological liberties, such as CASE/CASEII) in 3132 to go head to head in a tournament in the arenas to decide annually who in which weight class is king or queen of the junkheap. with host Marcus Fisher as announcer for the scenario, this tournament is set up to be ran with teams/Lances of four mechs. Planet(s) can any planet with an arena.
The tournament is divided into weight brackets for more balanced time. Divided into Light, Medium, heavy and assault weight categories. This Tournament is not only to test peoples knowledge of the construction rules but also their skill at playing the tabletop game with limited budget In terms of BV. At the moment things are slowly being finalized in my head in terms of Torunement rules but you can use this as a base for your own Retrotech Circuit if you wish.