Outland was a Sunday-only spin-off of Bloom County by Berkeley Breathed.
In September of 1989, a month after retiring Bloom County, Breathed began his second syndicated strip with a minor character from the previous strip. Ronald-Ann Smith, a little girl from the "wrong side of the tracks" in Bloom County, entered a grimy alley doorway that led to a cheery world known as the Outland.
In its earliest form, Outland had been intended to be an experimental strip for Breathed, featuring a channel for creativity in the forms of new characters and bizarre backgrounds (many of which initially resembled those seen in Krazy Kat). However, Opus the penguin returned in the strip's second installment, and Bill the Cat appeared just mere months after that. Before long, the premise of another world beyond a magic door had been lost completely.
Eventually, the strip began to evolve into something a little less weird and a little more familiar. Other characters from Bloom County, such as Milquetoast the Cockroach , Steve Dallas, Oliver Wendell Jones, and Michael Binkley, became major players in the strip. Some characters, such as Cutter John, made an occasional guest appearance. A few promenent members of Bloom County, such as Milo Bloom, didn't make an active appearance at all (Milo did appear in the second-to-last installment of Outland, but it was as a background extra on a bus).
Finally, in 1995, Breathed decided to end the strip and retire from cartooning. At the strip's end, Steve came out as a homosexual, and Opus returned to Antarctica to live with his mother.
Eight years later, Breathed abandoned retirement and picked up where Outland had left off. The result was the Sunday-only reunion strip, Opus.