Story & Art by Dave Sim.
Under a sorching mid-summer sun in Eshnosopur, Cerebus takes a challenge to stay in the ring for 20 seconds with the "Strongest Man in the Southwest", the so-called Bronze Bull, in order to win 5 gold coins. The large, sweaty fellow leaps atop the aardvark, but Cerebus' strength proves greater as he lifts the Bronze Bull over his head, flips him over, then wraps him in the ropes of the ring.
Cerebus demands his winnings from the ringmaster, but the skinny guy reveals that since his brother has a record of 270 wins and a tie, and they being poor farmers, they never bothered filling the purse to begin with! Cerebus is annoyed, as all he wanted to do was buy a horse to get out of the southland, and begins insulting the Bronze Bull, causing him to rip apart the ring as he grows enraged. Cerebus calmly offers to help the fat fighter lose 20 pounds through decapitation, and the hot and bothered crowd encourage him to do so. But quickly thinking, the ringmaster comes up with a compromise, much to the dismay of the crowd.
Soon, Cerebus rides off atop the shoulders of the Bronze Bull, thanking the Ringmaster, who asks only in return that when he gets to his destination, he turn his brother back in the direction of Eshnosopur and give him a little push.
From the Cerebus Archive Report #4
The exact location I don’t know specifically although I did at one time. Since it was intended for the Captain Canuck Summer Annual (somewhere between 1980 and 82) I had Cerebus do a quick southerly dip into one of the southern city states for a summer climate backdrop (everyone is sweating like pigs) either between the time he left Serrea (issue 4) and crossed the Red Marches (issue 5) or between the time that he crossed the Red Marches and before he entered Iest (issue 6). I might be misremembering but I think that’s how it went.
From Dave's intro in CBG
This is an unpublished Cerebus story which was commissioned by Comely Comix for The Captain Canuck Summer Special #2 (summer 1981). Comely went out of business shortly after approving the script and layouts for the story. A small blessing; his last letter suggested coloring Cerebus purple so that he would stand out in the color story!
Script and rough pencils printed in Comic Buyer's Guide #977, the August 7, 1992 issue. The finished story was never completed.
Cerebusfangirl Site: A reprint of the pages and script.