In late 1972, DC pioneered a new comic format: Tabloid-Sized. The first of these Tabloid-Sized comics also called Treasury Editions appeared before Christmas 1972 and featured Rudolph, the Red-Nosed Reindeer in all-new adventures. The 64-page tabloid was priced at $1.

The following summer DC returned to the format for a series of bi-monthly specials. The first of these specials featured Shazam and was labeled "Limited Collectors' Edition". DC used a numbering system on the tabloids beginning with #C-21. Like other Giant series of the time such as 100-Page Super Spectaculars, DC used a letter prefix and skipped several numbers. Issues #1-20 do not exist.

The Overstreet Price Guide lists the original Rudolph tabloid unofficially as Limited Collectors' Edition #C-20, though it was not numbered or labeled as such. In Comic Book Marketplace #69 Jon McClure postulates that the numbers on first issues of Giant series contained volume numbers. For example he speculates that Super DC Giant #13 stood for #1 Vol. 3.

If McClure's theory is applied in reverse to the Limited Collectors' Editions, #C-21 might stand for Vol. 2 #1. In this case Vol. 1 could be the Rudolph tabloid. This theory is a stretch, but might explain why DC numbered the comics as they did.

After 4 bi-monthly issues of Limited Collectors' Edition, DC began releasing two Tabloid-Sized comics together every other month. Both were part of Series "C", but one was called "Famous First Edition". Famous First Editions were exact reprints of famous Golden Age comics, beginning with Action Comics #1. After three issues published in the "C" series, Famous First Edition split off to become its own series, labeled "F".

DC continued to publish Limited Collectors' Edition until #C-50, 1976. After an 8 month hiatus, DC returned to the Tabloid-Sized format in 1977. Now priced at $2, the tabloids began alternating between reprinted material (still labeled Limited Collectors' Edition) and new material (All-New Collectors' Edition). Notably, All-New Collectors' Edition #C-56 featured Superman in a clash with Muhammed Ali specially priced at $2.50.

The final two issues of Series "C" were released to coincide with Superman the Movie in 1978. #C-61 was another Famous First Edition reprinting Superman #1. #C-62 was a behind-the-scenes look at Superman the Movie and was specially priced at $2.50. When DC returned to the Tabloid-Sized format briefly in 1981, they were labeled as part of DC Special Series, not Series "C".