Starquake

From the great abyss of a black hole emerges a danger of awesome consequences - a planet so unstable that if its core is not rebuilt the resulting explosion will render the Galaxy a lifeless wasteland. To the rescue, Blob, hero of the moment. This Bio-Logically Operating Being is chosen not for his super intelligence, not for his fearlessness nor for his super powers - his is the only spaceship available. Out to face danger he goes - trusty spaceship, flight-board computer and galaxy A-Z. Will he succeed? Will he be in time? He'd better, there's no other chance for the world.

Résumé

You are a BLOB (a Bio-Logically Operated Being) and are sent into the core of a planet in order to prevent dit from blowing up.