Ellie, the spirited and foul-mouthed heroine of post-apocalyptic action adventure game The Last of Us, was designed to echo the player's experience in the game's world while acting as a useful partner, Naughty Dog's Max Dyckhoff said at Game Developers Conference 2014.
The gameplay engineer explained the character's design choices in the GDC panel "Ellie: Buddy AI in The Last of Us." The first step, Dyckhoff said, was to treat the character as a person.
"To me, Ellie is my second child, and everything I did about her, I was thinking about what she was going through as a character and a human being as well," Dyckhoff said. "I tried to think what her relationship with Joel and the enemies would be, and if I was a person in this world what I would be doing."
Naughty Dog wanted Ellie to remain close to the player in any given scenario without being annoying and without "cheating " — teleporting or causing too much chaos. To that end, the character needed to be helpful in battle and not blow cover during moments of stealth.
"If she's just staying close to you, she's just going to be an escort quest," Dyckhoff said. "... If she does stuff, you're going to care about her even more."
"Ellie is, in my opinion, the star of The Last of Us."
Ellie's tendency to stick with Joel was influenced by developer's desire to keep players from blaming Ellie at any point. If she's always with Joel, Dyckhoff said, then her actions are no more stupid than the player's. Part of Naughty Dog's original design for the game included having to save Ellie even if she was far off-screen, but the mechanic was drastically scaled back to keep her from being a burden. The character will also occasionally offer support in the form of items — another element reduced to keep her from being an "ammo dispenser" — or even take down an enemy to save the player.
During stealth sections of the game, Ellie was designed to hurry to Joel for cover, while Joel will naturally put his arm over her as a way of protection. This animation helps build the relationship between the two characters.
"This is a father-daughter relationship you're looking at," he said.
Other small animations or actions that took place during non-cutscenes helped build Ellie's character as well. Ellie will explore different areas in the game on her own. She'll whistle, fidget and make off-handed comments as players wander. She is, in some ways, a representation of the player, Dyckhoff said.
"Ellie is, in my opinion, the star of The Last of Us," Dyckhoff said. "She's not world weary like Joel, the protagonist. She's seeing everything outside of the city for her own for the first time like the player is. She's afraid of scary things, much like we as players are too. We see violence and she's disgusted by it.
"To this end, she's a very important character. She is, to me, the real character in the game you should be thinking about."