In Nuclear War Simulator, one of my favorite creations to use and drop is something I’ve called the “Huangdi Bomb”. The name, after Chinese for “Emperor”, is a pun on Tsar Bomba. Only this has a bigger boom at 75 megatons. It’s also, in the backstory, a lot more advanced and sophisticated. Unlike the publicity stunt that was the Tsar, the Huangdi is a mass-produced, deployable weapon capable of fitting inside either an H-6 or large ICBM without issue.
It’s also, judging by the maximum payload of the Badger and its yield (the classic yield-weight calculation), the most efficient nuclear weapon ever made. As it has a multi-decade lead on the other megabombs, this isn’t surprising. As for how and why such a beast is used, the theories for the gargantuan warhead are hitting extremely large targets, making accuracy issues irrelevant for simple countervalue operations, improving warhead efficiency in a big design before trying to apply it to smaller ones, and contributing to deterrence by intimidating would-be-opponents with its yield.
In various NWS scenarios, I have about twenty Huangdis made overall, in both air-dropped and missile carried versions.