If something can be said about Pokémon Mystery Dungeon: Explorers of Sky, it would be the increased difficulty presented in this game. At the beginning of the game, the player will be asked whether they have played the series before. If the player answers yes, the game will start at an increased difficulty, in which enemies will appear more and cause more damage.
Increased difficulty can be considered as a welcoming change for this game. For the more experienced players of the series, adding a degree of difficulty would provide new challenges and prevent the game from being tedious and dull.