Valve’s Portal 2 project has posed a unique design obstacle for developer Valve: mental fatigue.
“It’s more difficult to pace Portal than it is a traditional shooter, definitely,” project manager Erik Johnson tells Develop.
“A game like Half-Life 2 has similar kind of issues around pacing, when people had combat fatigue – after fighting on and on and on – we would try to break that up with other elements.
“In Portal it’s trickier because you’re fighting their mental fatigue in the game."
The first Portal title, released in 2007, won widespread acclaim for its ingenuity and humour. Yet its inherent concept – having excelled in Portal’s bite-sized lifespan – will now be tested and stretched with Portal 2, a sequel promising a full-length AAA experience.
It means that pacing suddenly becomes a more prevalent development challenge, Johnson said.
"And you’re also fighting with a broad audience that will pick up the idea of the game at different paces, so we want to use the story as way to make the game work for everybody, and also make training elements fun.
“With Portal 2 we’re introducing so many new elements,” Johnson added, “that the pacing is a huge factor. There’s this tuning process to do this correctly.”
Unlike its predecessor, Portal 2 will be released without any commercial attachment to the star pulling-power of the Half-Life franchise. The title has been given an unspecified 2011 release date.
Johnson said that, in adding more and more elements to Portal 2, Valve is conscious of not losing the core identity of the game.
“It’s a huge challenge with Portal 2, to incorporate all these new elements in a way that doesn’t turn Portal into a different kind of game,” he said.
”Portal will always be fundamentally about thinking your way through a puzzle, and feeling really smart when you solve it.”