Stonar is the second level of the episode Turtle Soup from Jazz Jackrabbit.
Stonar is another huge wide-open area, with long vertical and horizontal stretches. Both the inside and outside areas are patrolled by the tougher red Armor Doofi, as well as the grabbers which rise from the ground. The second area is much more linear.
You can find the stage's secret level to the right of the first area's exit sign on a secret passage in the wall. This is another enemy-free area with lots of weapons, good for stockpiling on TNT.