Klinner

Doctor Isaac Klinner, commonly known as Klinner, is the main antagonist of Half-Life 2: Gordon Freakman, and later the main protagonist of Kleiner-Life.

He is one of the few surviving Kleiner Clones.

Events

 * Defeated by Gordon Freakman, the true villain of the first game.
 * Survives the encounter, ends up in the Kleiner cloning lab for unknown reasons.
 * Defeats Gordon Freakman, who apologizes for his actions and becomes Klinner's ally.
 * Blows up the Beta Citadel, assisted by Freakman, Mingebag, and Soldier Kleiner.

Fate
Although it seemed as if he'd been killed at the end of the first game, Klinner survived his encounter with Gordon Freakman.

Klinner, Gordon Freakman, and Soldier Kleiner reach a safe haven, realizing they're likely the only three people left alive. Klinner is given the choice to end the world, refuse to end the world, or be indecisive.

The second game has multiple endings. The ending the player gets is based on the decision they make here. Klinner's fate varies based on the ending achieved. As of right now, it is not known which ending is considered "canon".

End the World
Klinner hits the "Yes" button, and a bullsquid consumes the entire world. It is heavily implied that Gordon Freakman and Soldier Kleiner were killed, but Klinner's fate remains ambiguous. After the world's destruction, a scene plays that shows Klinner driving a car in an endless void. The player is forced to close the game, as this scene just continues forever. The void may possibly represent Heaven, Hell, or some kind of purgatory. However, it may also represent the empty space where the world used to be, meaning Klinner somehow survived the world's destruction.

Refuse to End the World
Klinner hits the "No" button, which screams at him and runs away. The choice, however, is confirmed, and the world continues. It is presumed that the three survivors continued their lives the best they could.

Indecisive - "Ask For Sequel"
Klinner hits the "Maybe" button, which unlocks another secret ending branch. He's given the choice between asking for a Gordon Freakman 3, committing suicide (and "stuff"), or shrug it off and say "I don't know" (written as "idk" in-game.) Klinner decides to ask for a sequel, resulting in him being immediately transported to another room. This room reveals that there is, in fact, another living being aside from Klinner, Freakman, and Soldier Kleiner - an unnamed NPC that shares Barney's model from Half-Life 2. This NPC may represent the developer, as he answers Kleiner's question (quoting the Heavy from Team Fortress 2), saying that a third game is possible, but nothing more. After this, the credits roll.

Indecisive - "Killself N Stuff"
Note: In-game, the button reads "killself n stu", due to the text being too large to fit on the button.

Klinner hits the "Maybe" button, which unlocks another secret ending branch. He's given the choice between asking for a Gordon Freakman 3, committing suicide (and "stuff"), or shrug it off and say "I don't know" (written as "idk" in-game.) Klinner decides to commit suicide (it is unknown what the other "stuff" is), resulting in the room being flooded with Navi enemies. The screen fades to black, and the credits roll. It is highly implied that Klinner was destroyed by the swarm of fairies.

Truly Indecisive
Klinner hits the "Maybe" button, which unlocks another secret ending branch. He's given the choice between asking for a Gordon Freakman 3, committing suicide (and "stuff"), or shrug it off and say "I don't know" (written as "idk" in-game.) Further demonstrating his inability to make decisions, Klinner hits the "idk" button. The credits roll.

Quotes
"Oh, fiddlesticks. What now?"

- Klinner when existing

Trivia

 * Klinner may be related to Doctor Hax from The Gmod Idiot Box.
 * Klinner's name is never spelled in-game, it can only be presumed.
 * If the player listens closely, Klinner's voice can be heard when cycling through menu options.