Maybe. Po Kong, it seems, only had Japan, so it is possible. But I can't help but wonder about remote or sparsely populated regions such as the Pacific islands or Antarctica.
Would the location of their portals have anything to do with their domains? If that is the case, I would guess the moon, or at least a place with very high altitude (so that it is close to the moon).
Possible, he could have had help from the other side.
Yeah, there are a lot of plot holes and unanswered questions on this show, as great as it was.
True, that's what I was thinking. Maybe since people have had bad experiences with the evil ones, they used a negative term for all non-human sorcerers, both bad and good. In the West, since such beings would have had similar features to biblical demons, the word "demon" got slapped onto them also, as it was the best word they would have had to descibe them.
I know! Why make it so they could be freed, and tell them how to do it and where to go?! Unless they come up with a good explanation, I am attributing that to a lapse in judgment or common sense.
Maybe they were just never mentioned because they did not show up in the series. That, or good/neutral ones were very rare.
If there are so in Chinese mythology, why not in the series?
I watched Xiaolin Chronicles, and I have to say that it was for the most part disappointing. Not only did they change certain events in the story, it did not do much respect for the characters, especially the villains. However, the creators of the show had their reasons and their share of difficulties with production (there is an article somewhere detailing these), so I can't get too upset at them about it.
It could center on a new group of Section 13 agents that interact with the original characters, especially Jade (who would be a mentor or big sister figure), and contend with new and old supernatural threats.
I know a reboot would make more sense if the creators wanted to target the same age group, but I feel that a continuation would more strongly appeal to those who grew up watching it (though it may be difficult or impossible to get the same voice cast). Also, the continuation could be a spinoff, set in J2's time period and probably give more focus to a new set of characters along with the original cast.
Since all serious threats were sealed away in the last episode, a revival is highly unlikely, and it would probably be better if it stayed that way.
However, nothing is impossible. Perhaps sometime in the future, Shendu somehow managed to escape again (he did it before, after all, even though it was never explained how), maybe by finding a rip in the space time continuum or getting destroyed again and escaping as a spirit. Also, if the sword that was used to banish him the first time was still out there, and it had fire demon qi, maybe that could come into play somehow.
I forgot to mention some other things that might lead to a continuation of the series: time travel and the Book of Ages. Maybe sometime in the future, something happens that undoes the events of the series finale that involves either of these factors.
In short: anything could happen.