The Adventures of Dino Riki is a very linear game. You play through the first three stages which introduce you to the three different environments that the game is played in; jungle, desert, and marsh. These first three stages are broken up into four subsections. If you die in these stages, you are returned to the beginning of the subsection in which you died. At the end of each stage is a boss that you must defeat before proceeding to the next stage.
The fourth stage is also broken up into four subsections, but each subsection is the length of the previous stages. If you die in these subsections, you are returned to the beginning of the subsection, no matter how close to the end you were. The first three subsections are harder versions of the first three stages, while the fourth resembles a second variant of the second stage. You must fight a boss at the end of each subsection of the fourth stage. The first three bosses are identical to the bosses from the first three stages. Only the fourth and final subsection has a unique boss.