Goku Uses Kaiō-Ken x100 in DBZ Movie 4
(He doesn’t actually say it in the film, but all signs point to that being the intent)
In the fourth theatrical Dragon Ball Z film, Goku somewhat infamously uses what later gets named “Pseudo-Super Saiyan” (in a film hilariously and literally called Super Saiyan Son Goku). During his battle with the evil Namekian Lord Slug, Goku’s hair stands up on end, he is surrounded with a strange aura, and his power seems to fly off the charts.
Goku soon gets control over himself, and alongside support from Piccolo, uses the Kaiō-Ken to defeat Slug (in a rather obvious nod to the way Goku defeated Demon King Piccolo).
While Goku simply yells Kaiō-Ken in the original dialog…
…fans worldwide swear up and down that Goku is using a hundred-fold multiplier (百倍 hyaku-bai) on the technique here in the film, supposedly backed up by a certain image:
Howl!! Kaiō-Ken x100!!! Smash evil!!
Will the Kaiō-Ken work against Slug, who’s said to be even stronger than Freeza?
Borrowing power from Piccolo, the Kaiō-Ken explodes!
Slug at last becomes a giant! The fierce battle finally enters its climax.
Where does this image actually come from, and if it was indeed intended to be the hundred-fold Kaiō-Ken, why doesn’t Goku say that in the film itself?
The Online Image Source
One of the earlier pieces online to showcase the image — dating back to at least 2012 — is an article dedicated to Slug within a Japanese fan’s battle power blog. Toward the end of the article, a thumbnail of the image is showcased alongside an explanation that the source of the hundred-fold Kaiō-Ken is the 1991 No. 12 issue of Weekly Shōnen Jump (more on this in a bit).
While clicking the thumbnail within the article brings up a larger version of the image, it is fairly cropped and presented only in black-and-white.
Proposed Images Sources
Before we get to the actual image source (there is indeed a source!), let’s take a look at a few other items fans speculate about — the black-and-white image is often passed around separate from its original Japanese blog source, leading fans to question its origin.
One of the first items that fans point to as a potential source for the image is the pamphlet from the Toei Anime Fair where the film first debuted. While the pamphlet does provide the usual complete overview of the film’s story, none of the text specifically calls out a hundred-fold Kaiō-Ken.
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Alongside collected volumes of the original manga itself, Shueisha also released “Anime Comics” of the theatrical films: screen shots from the films presented in a comic format, complete with printed dialog and sound effects. Fans often theorize that perhaps the “Anime Comic” release of Dragon Ball Z movie 4 either contained this black-and-white image, or perhaps even showcases Goku literally saying “Kaiō-Ken x100!”… but neither is true.
One final proposed source is the Daizenshuu series of guide books, but this specific splash does not appear in any of them, nor do they specify a hundred-fold Kaiō-Ken anywhere.
The Digest Video
Before we get to the splash image source, another contender enters the ring: the Dragon Ball Z movie 4 digest video!
These short recap videos were originally produced for VHS releases (and were later collected on the Dragon Box DVD release) and featured narration — generally Masako Nozawa in-character as Goku — explaining the overall plot of the respective film. In addition to the new narration, the digest videos don’t always necessarily feature direct dialog from the film…
… such as this example of Goku using the hundred-fold Kaiō-Ken!
The Actual Image Source
Thankfully, we here at Kanzenshuu own a plethora of original Weekly Shōnen Jump issues, and were able to verify for ourselves that the image in question does in fact come from the 1991 No. 12 issue! We actually missed it on first glance, because it doesn’t come from an article: it comes from the foldout poster in the front of the issue… where it is presented in full color!
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The 1991 No. 12 issue was released 26 February 1991 (also containing Dragon Ball manga chapter 314), placing it less than two weeks ahead of the film’s debut on 09 March 1991. There is nothing particularly special or notable about the image itself… outside of its hundred-fold Kaiō-Ken notation!
Conclusion
We have no idea if perhaps the original script for the film specified a hundred-fold Kaiō-Ken, but something certainly exists in the production materials noting this specific phrase, as it pops up in both the digest video and a promotional splash.
This was ultimately not stated directly in the film itself, but considering how much lore and contextual material we know was produced for at least the earliest Dragon Ball Z films — for example, entire background stories for all of Tullece’s henchmen in Dragon Ball Z movie 3 which go unstated in the film! — as is often the case, it is up to the individual fan whether or not they want to consider this external documentation in their personal analysis.