Batman has worn many capes, cowls and costumes over the years, from his classic grey look to the black costumes of most of the movies. These suits reflect his darker and grittier stories, with the black costumes especially reflecting his more urban and stealth-based premise. One costume and its accompanying story, however, completely did away with both stealth or anything remotely cool.
The costume for the Batman of Zur-En-Arrh is a garish, utterly ridiculous series of threads that make The Dark Knight more fitting in a psychedelic dream than a street level, Gothic nightmare. Despite the ridiculousness of its appearance and its origin, this suit ironically came back in a much darker form due to Grant Morrison.
Who Was Tlano, the Batman of Zur-En-Arrh?
Tlano, the Batman of Zur-En-Arrh, debuted in Batman #113. Created by France Herron and Dick Sprang, this Caped Crusader had a costume and training very similar to the one of Earth. Bringing the human Batman to his homeworld of Zur-En-Arrh, Tlano hoped for assistance against robots used by another alien race. While on this strange new planet, Earth's Batman found that he suddenly developed incredible powers like that of his friend Superman. After defeating the would-be alien conquerors together, the Batmen parted ways, with Tlano giving Bruce Wayne a Bat-radia as a token of their friendship.
The Batman of Zur-En-Arrh had perhaps the most laughable Batman costume ever. Instead of greys, blacks or even dark blues, his Batman costume was purple, red and yellow, rendering his fearsome qualities nonexistent. Needless to say, this ridiculous concept lay dormant for quite a while after being introdued in the Silver Age of comic books. However, this costume concept would reappear many years later under the stewardship of writer Grant Morrison.
Grant Morrison Made Zur-En-Arrh Batman Much Cooler
The modern interpretation of the Batman of Zur-En-Arrh was introduced by Grant Morrison, who radically reimagined the idea in Batman #681. This was in an attempt to legitimize all aspects of Batman's publication history, even the silliest sections of the Silver Age. It's revealed that in the Post-Crisis continuity, Zur-En-Arrh is a sort of "backup" personality for Bruce Wayne if he's ever mentally compromised. The odd name for the trigger phrase stemmed from Bruce mishearing his father's last words when Thomas stated that "the sad thing is they'd probably throw someone like Zorro in Arkham."
Once "triggered" by the Zur-En-Arrh phrase, Bruce reverts to a far more savage and violent persona. Making a makeshift Batman costume for himself, the bright colors of the piecemeal suit are of course those of the classic Zur-En-Arrh Batman. The gaudiness of this suit is also compared to the theatrics of Robin, and it's meant to ironically be a ferocious threat to anyone who sees it. Zur-En-Arrh refers to himself as Batman with Bruce Wayne "out of the equation," and he's constantly spoken to in hallucinations by none other than fellow Silver Age reject Bat-Mite. Bat-Mite is supposed to mentally counter Zur-En-Arrh, as without Bruce Wayne's inhibitions, he's far more likely to use lethal force on anyone who stands in his way.
Since Morrison's run on the book, there have been adaptations of both versions of Zur-En-Arrh Batman. The cynical deconstruction that Morrison used showcased how even the most inane Silver Age concepts can be reused in an interesting and modern way. Another more recent example is the new version of Topo in Geoff Johns' run on Aquaman during the New 52. This series changed what was once an octopus friend of Aquaman's that played musical instruments into a gigantic octopus-like monster that's summoned by a musical instrument. Hopefully more writers will feel free to repurpose these old ideas for new generations of readers, though as with the case of Zur-En-Arrh Batman, they definitely have to be changed in order to actually be usable and relevant to the story.