This is a single-player adventure game that tells the story of a ghost. This game takes place in Eternity, a place that exists outside of space where all souls eventually end up.

The story follows Hauntii, a meek but curious ghost that has just arrived in Eternity not really knowing much of anything. Eternity is a place quite different from Earth. No ghost can really die, however they can be led astray a number of ways, and even corrupted into hellish fiends.

There is a mysterious race of glowing creatures, known as Eternians, who guide lost souls to an ominous central tower, where they appear to ascend to a higher plane. Eternians appear much like angels, but nobody truly knows who they are or where they come from.

• Relax - Hauntii has many faster, high energy moments, but that's not all there is to it. This game invites you to ease into a more relaxed, contemplative mood as you explore the other-worldly landscapes in Eternity.
  
  
• Explore - Level design is kept tight but open-ended. Explore the rich stages in Hauntii, taking your own path, knowing there will always be something around the corner for you to find. The stage design philosophy is to go smaller rather than bigger. With smaller stages, every aspect can be carefully crafted.
  
  
• Haunt - A key mechanic in Hauntii is, well, haunting. As a ghost, you can haunt statues, creatures, lamps, and a myriad of other things. We don't limit you to how you can solve the challenges ahead, and with haunting there are endless ways to approach them.
  
  
• Collect - To make progress, you must build the Constellations that contain the story of Hauntii's past life. Constellations are built from Constellation Bits, which can be found by exploring, solving challenges, or trading with other ghosts.