Hidden Island 6 shares Plant Kingdom's design. The island is a blue-skied untamed jungle with enormous plants like leaves, flowers, plant stems and fungi everywhere. All around are ginormous undergrowth like moss stalks and flat fungi stretching into the sky, leaving the jungle bottom covered in darkness with only a few bio-luminescent fungi to illuminate it. Along with fertile brown soil and small round hills, thick grass covers the ground and ledges like a neat blanket.
Like most other Hidden Islands, Hidden Island 6 is a short stage which can be finished in less than a minute. However, it does not focus on a certain gameplay style or gimmick.
Hidden Island 6 borrows several exclusive gimmicks from Plant Kingdom. These include mushrooms and stem tubes (based on Winding Tunnels/High-speed elevators) that suck up the player at one end, transport them through the tube, and launch them out of the other end with a burst of pink petals. The latter lets the player use Trick Actions after being launched out. There is also a humanoid tree that scoops the player up and tosses them sky-bound. Trick Actions can be performed once released. Regular gimmicks include Grind Rails and Dash Rings.
Follow first the path that leads across a bottomless pit which eventually launches the character to the other side. While in midair, the player can use Blaze's Axel Tornado to reach a higher route marked by a Spring; otherwise, the player ends up on the lower route. After crossing a shuttle loop, the player can then either follow a new upper route to the right or go to the bottom.
Following the shuttle loop on the path after being flung by the humanoid tree, the player enters a new section where they can reach an upper route marked with a Spring chain or follow the bottom. Either way, they will arrive at a stem tube that leads to an open area where the Treasure Chest is.