Prototype versions of the Xbox One controller contained smell features and image projection.
As part of a VentureBeat feature on the controller's development, Xbox's general manager for accessories Zulfi Alam revealed how some of the "hundreds" of different prototypes had unique capabilities.
"We had a whole bunch of brainstorm sessions and built hundreds of models," Alam said. "We looked at concepts like adding displays to the controller. We looked at concepts like adding smell.
"We built small slugs of different types of smells that could actually come out of a controller. Like, as you walked through a jungle, you'd smell the flora."
Other prototypes incorporated features that ended up in rival controllers, such as speakers (added to Sony's DualShock 4) or a second screen (as featured on the Wii U GamePad), but ultimately both ideas were scrapped by Microsoft.
"You've got a great TV with a better speaker than we could ever put in this controller," explained Microsoft senior industrial designer Quintin Morris.
"And it made more sense to [not make players look down at a display], keeping the user's attention on the TV. We really want them to be immersed in the experience that's happening in front of them.
Morris added that with an extra screen, "you're burning battery life like there's no tomorrow - not a great idea."
VentureBeat also reports that one prototype featured "a tiny projector which would beam out ambient visuals around the player".
In a previous interview with CVG, Alam explained the benefits of the new controller's impulse triggers, which feature several small rumble motors scattered across the pad, allowing for more subtle force feedback in localised parts of the controller.
"The palm of your hand, which is usually what picks up the force feedback first, is not the most sensitive part," Alam told CVG. "It's the tip of your fingers that's the most sensitive, so if you really want high-fidelity haptics, you need to find a way to get rumble at players' fingertips."