This transformation did not come out as such in Dragon ball, but Toriyama came to draw it
Dragon ball has so much longevity that many already know some of the key elements of the entire franchise, although there may be some other detail that is known over time such as revealing the origin of Goku’s first villain. And it is not for less, since with so many elements there are details that can be escaped such as the only character at Goku, although if something is clear about the followers of their community is that Prilin is not this character*.
Given this it is quite possible that This name does not sound like anything And the truth is that it is not for less, since officially It has never been seen in the anime or manga. However, perhaps some remember that in the Buu saga, Goku taught the dance of the fusion so that Goten and Trunks form Gotenks. However, to make sure they learn this technique, Piccolo asks Krilin to do itso that they do it without results, since it requires that The two warriors have a similar shape, level of power and appearance.
The fusion between Krilin and Piccolo is called Prilin and was drawn by Akira Toriyama
Now what would have happened if the fusion had been carried out? Well, the result is PRILINa character designed by Akira Toriyama as a joke and takes elements of both Piccolo and Krilin. In fact, it can be seen that the size of this character is small as that of the human, but with the face of the Namekiano along with his ears, although it is distinguished from this by having the marks on the forehead of Krilin.
It should be noted that Prilin never came out in the series nor in the imagination of the characters unlike what happened with Gokule, the fusion between Goku and Mr. Satan. You can take a look at the character below:
Prilin is the fusion between Piccolo and Krilin that never came out in the anime or manga
It should be noted that, despite everything, The Dragon ball Fusions video game was responsible for breaking the rule of similaritybeing here where Prilin was able to shine at last. Of course, being an unofficial game within the canon, it cannot be said that the character can appear in Dragon ball.