One morning, Sonic is contacted by Tails who warns him that Dr. Eggman has obtained a Chaos Emerald for an unknown purpose but the signal between Sonic and Tails becomes unstable. Tails requests that the hedgehog should come to his research facility. Sonic however arrives too late, as he witnesses Eggman kidnapping Tails and escape with him on a helicopter. After Sonic follows the doctor up into the skies, he notices a flying fortress and heads there, suspecting that Eggman and Tails are also there. Without a doubt, Sonic found Eggman and came to Tails' safety while the doctor taunts he obtained all the other Chaos Emeralds and there is one left to find. Tails suspects that Eggman is heading towards Angel Island which is the location of the last Chaos Emerald.
Sonic and Tails travel there but Eggman already beats them to it and demands Knuckles to hand the Chaos Emerald. Knuckles spots the heroic duo and asks what they are doing only to realize that Eggman snatched the Emerald at the moment. Now possessing all of the Chaos Emeralds, Eggman then reveals to the heroes that he plans to harness the Chaos Emeralds' energy to create the "Brainwash Beam" as part of his world domination schemes before taking off. Sonic and Knuckles argue for a bit only for Tails to stop them. Tails suggests that Eggman needs to head into outer-space in order for the Brainwash Beam to cover the whole world and also knows that Eggman has a space station at South America to launch a rocket from there.
Sonic, Tails and Knuckles headed to South America and sure enough, they found Eggman there but unfortunately for the heroes, Eggman has already prepared the rocket launch and is heading towards space. Not willing to give up, Sonic asks if there is a way to catch up to Eggman and Tails replies that it is possible using the space station's controls. Sonic uses it and launches himself up into space and eventually catches up with Eggman and destroys his space satellite containing the Brainwash Beam, scattering the Chaos Emeralds around Earth before falling back down to Earth himself.
Sonic recovers from his fall and receives praises from Tails and Knuckles. When Knuckles asked if Sonic had the Chaos Emeralds, he replied that they all scattered. Sonic then searched around the world and managed to find all but one of the Chaos Emeralds. Suspecting that Eggman still has the last Chaos Emerald, Sonic returns to space and successfully confronts Eggman one last time. The hedgehog triumphs over the evil doctor and reclaims the final Chaos Emerald. Dr. Eggman then disappears but not before swearing revenge. Receiving praises from his friends, the trio of heroes believe that they have not seen the last of Eggman yet.
Sonic Jump features a gameplay unlike any other Sonic games, similar to Rainbow Islands; the player must guide Sonic up through the levels while primarily controlling his left and right movements. Whenever Sonic lands on a platform, he will automatically jump off it. Traversing upwards is a one-way affair as the screen scrolls with Sonic's movements; he cannot go back down. Hence the bottom of the screen essentially acts a constant bottomless pit; if he falls off-screen, he will lose a life. Some different types of platforms include ones that fall apart after one jump while others bounce him up higher than usual.
The Rings in this game still maintain the same functionality seen in previous Sonic games as Sonic will encounter Badniks which can only be defeated by jumping at them from below; touching them while falling will cause Sonic to take damage and lose some of his Rings. Points are earned by defeating badniks, gaining Rings and clearing levels quickly. Completing a level with fifty or more Rings allows the player to earn a fragment of a Chaos Emerald.
If the player takes too long to finish a stage, the water level rises.
Sonic Jump had a mixed reception, receiving a 5 out of 10 from IGN. They noted that the game has "sluggish and occasionally inaccurate" controls and is generally "quite dull".
- The Sonic sprites are ripped from Sonic Advance, while the Badnik sprites are ripped from Sonic Advance 3.
- On the title screen, Sonic's eyes are blue, not the usual green.
- The turquoise-colored Chaos Emerald is replaced by a black-colored one.
- This is one of the few games where the player does not lose all of their Rings when hit.
- Sonic Cafe website (Archived)