When spells go awry horrific things happen. So what happens when a botched Prismatic Sphere crosses an ooze? You get the Prismatic Ooze, a horrid and chaotic creature that is constantly morphing.
Armor Class: 7 
Hit Dice: 3
Attacks: Strike (2d6)
Saving Throw: 14
Special: Immune to charm, fear, confusion and similar spells (it’s mindless). Random special ability.
Challenge Level/XP: 8/800
At the beginning of the Prismatic Ooze’s turn, the GM rolls (1d10) on the following chart to determine the creatures special ability this round.
1 to 2-No special ability this round.
3-Red: Attack does +1d6 fire damage. Immune to fire.
3-Orange: Attack does +1d6 electrical damage. Immune to electricity.
5-Yellow: Gains an additional 1d4 attacks. Its Armor improves by 1d4.
6-Green: If struck by the ooze, the target must make a Saving Throw or be blinded for 1d6 rounds. Any attack that damages the ooze causes an acid splash. All characters adjacent to the ooze must make a Saving Throw or take damage equal to half the damage that the ooze received.
7-Blue: If struck by the ooze, the target must make a Saving Throw or be turned into stone. The ooze takes half damage from weapon attacks.
8-Indigo: If stuck by the ooze, the target must make a Saving Throw or be under the influence of a Confusion spell for 1d6 rounds. The ooze is under the effects of a Mirror Image spell. The images will last for 1d6 rounds.
9-Violet: If struck by the ooze, the target must make a Saving Throw or die. The ooze has 75% Magic Resistance.
10-Roll Twice and apply both results with common sense. Ignore this result if rolled again in the same round.