The director of Kirby: Triple Deluxe has explained why Nintendo's lovable pink rogue is often angrier in the West.

Box art for Kirby games usually shows the rotund character wearing a winning smile in his homeland of Japan. But the artwork is often changed for North America and Europe - here he has angry eyes and a scowl.

"For the Japanese versions we are, at [Kirby developer] HAL, involved in everything throughout development, including the package design," director Shinya Kumazaki told Gamespot. "The most powerful image of Kirby is that cute image, we think that's the one that appeals to the widest audience.

"While it does start cute, we know there is a serious side to Kirby as well," Kumazaki continued. "What we have heard is that strong, tough Kirby that's really battling hard is a more appealing sign of Kirby [in North America], so that's what we feature in the US."

For comparison, the Japanese and US/European art from Kirby Air Ride and Kirby's Return to Dreamland. Note the grumpy face.

Angry Kirby also took centre stage for Kirby Mass Attack.

But not all games have followed the trope - Kirby: Triple Deluxe features the same grumpy Kirby on both the Japanese and international box designs (right).

Kirby's Epic Yarn, meanwhile, finally saw the pink character appear cheerful in all regions.