During the war between the Re'nar and Ju'wes in the Matrua Nebula, Mac'atyde did many terrible things. After the war ended with victory for the Ju'wes, he decided that he liked what he had become and continued to hunt others for sport. A Ju'wes pursued to take him to stand trial. They fought in space but their ships were pulled through a time eddy engineered by Mac'atyde. Both ships were destroyed after crashing on 19th century Earth. Using a shimmer suit to disguise himself as human, he killed a woman in Whitechapel. The Ju'wes caught up to him and took the place of Sir Charles Warren so he could follow the case and wait for the Ripper's final historical murder.
On 30 September, he killed both Elizabeth Stride and Catherine Eddowes but was interrupted both times. He wrote the Goulsten Street message in order to implicate the Ju'wes. He promised the Eleventh Doctor that he would take his TARDIS and Amy Pond. Mac'atyde overheard Amy trying to warn Mary Warner that she would be next.
On 9 November, Mac'atyde killed Mary Kelly while the police were keeping vigil over Warner's residence. He then abducted Amy and Mary Warner. An alternate timeline was created where he killed them both and dragged their bodies elsewhere on the 10th. A 2011 expert noted there were five additional murders he considered canon.
The Eleventh Doctor tracked his kryon radiation to a small cellar at the moment Amy and Mary had made their escape. The Ju'wes fought Mac'atyde who revealed that he intended now to have all of London sucked through the portal. The Doctor found and stabilised the portal and the Ju'wes pushed him through. Both died in empty space. (COMIC: Ripper's Curse)