Porunga is the Eternal Dragon of Namek summoned when all the Dragon Balls of Namek are gathered. Compared to the Dragon Balls of Earth, the Namekian Dragon Balls are quite large, being more towards the size of a basketball rather than the size of a small grapefruit. Also, since a year on Namek is only 130 days (as opposed to a year more than twice as long as that on Earth), the Namekian Dragon Balls can be gathered more often than the ones on Earth, and thus, Porunga can be called on more often than Shenron.
As far as physical characteristics go, Porunga is much more brutal-looking than the dragon of Earth, Shenron, with a heavily muscled upper body. Instead of looking snake-like in appearance, like Shenron does, Porunga appears to be more alligator-like. He also has a large fin down the center of his back, and large spikes on his shoulders and head, as well as two antennae on his forehead.
Like Shenron, Porunga is good and kind-hearted, but being that he is a dragon, he has a temper and sometimes comes off as impatient. However, he has demonstrated a greater eagerness to grant wishes, and also is more friendly and patient than Shenron, who tends to be grumpy and even more impatient when a summoner takes an inordinate/excessive amount of time to make a wish.
Grant-able wishes Edit
Besides being more friendly than Shenron and being able to be summoned more often, Porunga is also stronger than Shenron in that he can grant three wishes instead of one or two.
Though he doesn't actually appear or get mentioned by name, it's stated that Slug and other Namekians were exiled with the help of the Dragon Balls. It's not actually originally explained what they did, but the FUNimation dub seems to indicate it was for misusing their powers.
Initially, Porunga had ability to bring only one person back to life at a time (though he could bring people back multiple times), as compared to Shenron who can bring back an unspecified number of
people but can only do so once. Later, Porunga's power is strengthened to bring back as many lives as needed. The Elder Kai criticized this as "a blasphemous act that disrupts the order of nature" (the meaning of this would later be explained in GT) but did not seem to mind after that.
Like Shenron, Porunga's wish-granting powers are limited by the power of his creator, Guru (and later on, Elder Moori). Any wish that is encompassed within his creator's power is able to be granted.
It could be argued that Porunga is morally opposed to killing anyone who is good. When everyone had thought Goku had died when Namek exploded after his fight with Frieza, they asked Porunga to bring him to the check-in station in other world, from where Goku could be wished back to life and would end up on Earth. However, Porunga refused, as he not only informed them that Goku was alive, but that if he moved Goku to the check-in station, Goku would die. This is another potential contrast between Porunga and Shenron, the latter of whom had been known to be more threatening (even threatening to kill a good character in one instance if a wish wasn't given — something that Porunga has never done).
While Shenron also has this limitation, it has been shown that Porunga will not bring somebody back to life or back to Earth against their will. For example, when Bulma and Dende asked Porunga to bring Goku back to Earth after Namek exploded, Goku requested to not be brought back to Earth. Porunga honored Goku's request and did not carry out the wish.
Also, wishes must be given in the Namekian language. This limitation prevented Frieza's wish for immortality from being granted, so it is possible that this may be some sort of safeguard against off-worlders misusing the Dragon Balls. Porunga is still able to respond to inquiries regarding his wish-granting abilities that are not made in the Namekian tongue, such as when Dende made a wish during the end of the Kid Buu Saga in the common language, and Porunga responded with "Such a wish is well within my power to grant. Okay." However, Dende still had to deliver the wish in Namekian before Porunga would grant the wish (He was forced to speak it in the common language because Porunga didn't quite understand the Namekian Translation).
- In the credits of Budokai Tenkaichi Porunga's name is spelt Polunga.
- Though Porunga cannot accept wishes made in the common language, he is a fluent speaker of it, and even responds to Namekian wishes using it.