Difficulty is "like heroin" in the XCOM universe.
"I guess it's like heroin at some point," joked Jake Solomon, lead designer on Firaxis' XCOM: Enemy Unknown project. "You need the hardest shit, and you keep wanting more and more." He was talking about challenge, and how some things are sacred in the XCOM universe, permadeath being one of them. The way he tells it, you need a factor like that to make the game worth playing. Otherwise the whole thing's less of an achievement than it could have been. There's a place for narrative-driven games, but that place isn't where XCOM needs to be.
In its heyday, the XCOM franchise was about managing resources and the consequences of making mistakes. The enemy was out for blood, and if you wanted to beat them, you had to be just as clever and ruthless as they were. This, says Solomon, is what Firaxis' contribution to the franchise is all about. "If there aren't real consequences there," he says, "then you can't have real successes either."
XCOM features turn-based combat against invading aliens, where your squad either tracks down the threat and neutralizes it, or faces the consequences of failure. Real consequences means that when resources are spent, they're gone for good; when friendly NPCs get discouraged by your lack of success, they abandon your cause. That means the player has to fight for every victory. On the other hand, the adrenaline rush the player gets when they make the right choices and see the results play out is what will keep them coming back to XCOM, like junkies in need of a fix.
"In terms of the game's mechanics," says Solomon, "you need to make sure you have things like permadeath." So expect to feel a sinking feeling in the pit of your stomach when you realize that the only equipment you have that can hurt the enemy is on the corpse of a squaddie that's being covered by the enemy's sharpshooters, but comfort yourself with the knowledge that clever planning and resource management will turn things around for you. Or as Solomon puts it "that's what made games like XCOM special."
XCOM: Enemy Unknown is due out October 9th, 2012.