Without its deleted finale, Metal Gear Solid V has no ending at all

They say that before you embark on a journey of revenge, you should dig two graves. This is why Metal Gear Solid V: The Phantom Pain has two endings. At the climax of the game’s first chapter, Venom Snake and his Diamond Dogs take their revenge on the villainous Skull Face and the credits roll—but then the game’s second chapter starts. Snake’s advisors grow cagey, change their minds about who their real enemy is, and continue accepting meaningless gun-for-hire work. Over time, the group disintegrates. Members are exiled or run away, and an outbreak of untreatable and contagious parasites forces Snake to slaughter many of his own soldiers. Finally, Snake learns that he’s not the legendary Big Boss at all but a hypnotized body double. By the end of chapter two, Snake has lost everything: his purpose, his friends, even his identity. Here the game ends again, burying Snake in the proverbial second grave.
This is how the game ends as it exists now, but it wasn’t the story’s intended conclusion. Appropriately, given its subtitle, The Phantom Pain is missing parts. A 51st and final episode was cut from the game due to time and budget constraints, but a video depicting the unfinished content was included as a special feature in the game’s collector’s edition. That lost ending would have significantly changed how the story and its themes played out. Not only would it have tied off plot threads that are left hanging in the existing ending, but it also would have elevated The Phantom Pain from a comparatively straightforward anti-revenge cautionary tale to a much richer meditation on selfhood, legacy, and truth. To say MGS5’s ending is abrupt would be too kind—episode 51 was so vital to the story of The Phantom Pain that it’s almost more accurate to say that without it, the game doesn’t have an ending at all.
In the lost episode 51, the Diamond Dogs find Eli—the boy warlord cloned from Big Boss, the legendary soldier whose body double you’ve been playing as throughout Phantom Pain, unbeknownst to you until the very end—and the Metal Gear he stole from them hiding on an island that’s been contaminated by deadly lab-grown parasites. This episode would have climaxed with a battle against Metal Gear Sahelanthropus, the nuke-wielding bipedal tank, and Eli, who reveals his patricidal motivation before the battle begins: “You don’t get the last word, Father. I’ll break the curse of my heritage.” After Snake’s victory, the Diamond Dogs reclaim Sahelanthropus, and the humiliated Eli lashes out at Venom Snake—“I’m not me. I’m just a copy of you.”—not realizing he isn’t the real Big Boss. Snake, pitying Eli and recognizing himself in the child’s identity crisis, leaves him a handgun with a single bullet, expecting never to see him again. Instead, Eli escapes, living on to become Liquid Snake, one of the series’ recurring villains.