Larry Hama and Michael Golden's "Bucky O'Hare and the Toad Wars" began as part of a comic book anthology series, "Echo of Futurepast," produced by Neal Adams and Continuity Comics in the mid-'80s. It appeared serially in the first six issues of that comic, running from May 1984 to July 1985. The complete set of pages from this was published as a large-sheet graphic novel in 1986.
In 1991, the story was mostly reissued, in an expanded form, as a five-issue comic book miniseries. (Issue #5 ended most of the way through the graphic novel's story and said "to be continued"; an unpublished issue #6 would have finished the original story.) Contunuity Comics took the art from the original run, made the panels bigger, and expanded the story by adding more dialogue. At least a little original art was added as well, and the breakpoints between some issues was slightly different.
The UK comic from around this time used the original US material for issues 1-6. (Each of the first five issues reprinted the exact panels from the corresponding US issue -- with slightly altered dialogue and a different breakpoint between issues #1 and #2 -- and issue #6 finished the original graphic novel story.) Issues #7-#20 were then made from scratch, featuring some of the "new" characters from the cartoon but not necessarily following its plotlines. They were written by Peter Stone, penciled by Andre Coates, and inked by Joel Adams (Neal Adams's son).
In 2006, Neal Adams released the Bucky O'Hare comics in a "manga" format (referring to the size of the book). It reprinted the graphic novel material in black and white and added issues #7 and #8 of the UK comic. The copy on the back doesn't quite match up to the book's contents, but it's currently the only Bucky O'Hare material in print.
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