Into The Breach is fiddly, tactical game where I have often taken three or four minutes to consider a single turn, so watching someone beat the game in less than 12 minutes is pretty impressive.
A runner by the name of Darn is responsible for this run, and they currently hold the world record for fastest time in the “Custom Squad, ANY” with the “two island, easy” qualifier.
While Into The Breach speedrunning is fairly new since the game only released in February of this year, but the community seems to be sorting out some accepted categories. A custom squad allows a runner to optimize their mechs to clear boards as quickly as possible, and the addition of an artillery mech that freezes enemies gives players a huge advantage (this has also led to a “no ice artillery” category).
Completing two islands on the game’s easy mode is also the fastest way of clearing the game. In normal play, doing more islands will help equip players for the final battle of the game, but for a speedrunner, that all just gets in the way.
Darn is also a notable runner in the nascent Heat Signature community, holding the record for that game’s any% category.