"Final showdown" refers to the last and decisive confrontation between two opposing parties or individuals. It is the ultimate battle or contest that determines the ultimate winner or outcome. Full definition
Simply put, it not only holds its own, but improves on the formula in several key respects, from a politically engaged villain to an emotionally grounded final showdown. (variety.com)
This all builds to an intense final showdown, wherein the damage you've done on the boss up to that point actually makes a difference. (shortpause.com)
During the demo, players were eliminated one by one until only one squad member remained on each side, leading to a dramatic final showdown. (techradar.com)