Iwata Asks," in which Nintendo CEO Satoru Iwata politely interrogates designers and employees about recent games, there's an interesting discussion regarding the difficulty of Kirby's Epic Yarn. Specifically, it's about how developer Good-Feel cut out deadly traps and objects in order to preserve the game's endearing, fluffy and fun atmosphere.
"As a team, we were extremely opposed to the idea of an action game where the game wasn't over when an enemy got you," said producer Etsunobu Ebisu. "We debated that for quite a long time." At first, levels in Kirby's Epic Yarn (formerly Fluff's epic yarn) were full of thorns, a thrilling contrivance that didn't sit well with the game's warm aesthetic. Later, however, "we thought it would be fine if we just made a fun game the way we're good at," Ebisu explained.
This led to the introduction of a different characteristic in obstacles, with failure to avoid them resulting in the loss of Kirby's collected beads. You can collect them once dropped, but the in-game currency -- used to unlock bonus levels, for instance -- acts as a strong measure of success at the conclusion of a stage. "When serious gamers play, they want to clear a level without any mistakes like running into enemies, so this game is made so you really feel regret when you run into enemies and a strong sense of achievement when you clear a level without any mistakes," said producer Nobuo Matsumiya.
Or, as Iwata succinctly put it: "As a gamer, it's humiliating to bump into an enemy."