Jelly Boy was one of those "lost" platformers of the 1990s. It was a game of exceptional quality that got lost within the many, many poorly designed 2D platformers that plagued the 1990s. Subsequently this game, like Plok or Skyblazer, went largely unnoticed by the general gaming public on release. Jelly Boy puts in the control of a jelly baby with morphing powers, like if A Boy and His Blob merged together in some ungodly ritual. His quest is to find various items inside a weird factory so that the elevator doorman will allow him to go up and meet the dude in charge. The most important items are musical notes. These are like the rings in Sonic The Hedgehog, as they'll serve both as an extra life (at 100) as well as a one-hit shield.
Source: Wikipedia, "Jelly Boy", available under the CC-BY-SA License.