Gamers are a tough crowd to please. If a sequel is too similar to the original, fans will ask, "Why wasn't this an expansion pack?"

What separates a good sequel from a mediocre one? Developers need to polish and fix the original's flaws, but also come up with a new angle, balancing the familiar with the novel. "Ori and the Will of the Wisps" does that adeptly.

The follow-up carries over the fine-tuned platforming of 2015's "Ori and the Blind Forest" and expands on it by improving the combat and adding depth to the characters. Although "Will of the Wisps" appears to be a Metroidvania-type game, Moon Studios modeled the sequel after a different game, "The Legend of Zelda."

"Will of the Wisps" begins almost immediately after the end of "Blind Forest" with the birth of an owlet named Ku. Ori, Naru and Gumo take care of the fledgling owlet and try to raise it, but Ku is saddened by her inability to fly. Ori fixes that with a gift of a feather from Ku's late mother, Kuro. With the keepsake tied to its wing, the two set off and explore the world outside of Nibel. Unfortunately, a storm hits and the two end up separated.

That mishap kicks off the first act, which focuses on Ori reuniting with Ku, and that sets up the basics of "Will of the Wisps." Players will notice an emphasis on combat as Ori uses a spirit sword to slash at foes and a bow and arrow to target them from a distance. Players can sub in other weapons and abilities depending on their playstyle and that gives each play-through a different feel. That's amplified by the concept of Spirit Shards that players collect — rewards for exploration or solving puzzles that help make "Will of the Wisps" easier in areas such as combat and traversal.

Moon Studios opens the game up in the second act, and players are given free rein to venture through five themed areas with the goal of finding the wisps of Niwen. These spirit pieces are the only way to stop the decay that has ruined life in the area.

The freedom in "Will of the Wisps" leads to some difficulties. Initially, players will run into tough boss fights or they could find an area that needs another ability to access. If that happens, players have to backtrack and meander through new zones to find power-ups to boost spirit energy and life.

Everything players learned collecting the wisps will be important in the final act at Willow's End, as Ori deals with a level where the floor, walls and ceilings are essentially covered with lava. They'll have to use their abilities to whip across platforms or catch projectiles and redirect them at adversaries.

Despite the variability involved, players will find that the progression of challenges is manageable. "Will of the Wisps" is a near-pitch-perfect sequel that delivers everything fans and newcomers would want.