The Shadowkhan are rarely consistent in how effective they are, sometimes a handful are more than enough to subdue Jackie and crew, other times they aren't of much concern. By the fourth season, which delves into their history and how Shendu had control over them, you realize that they are effectively puppets. Whenever they are actually competent (such as when Jade inadvertently gained control of them) it is because their controller is nearby and can better direct their efforts. All the other times they are on long range missions and are simply not as independently "smart."
(Season 4) Why were episodes 9-12 of 13 throwaway episodes? Because Tarakudo was chilling on his ass waiting for the nine masks to be united! If you assume that each mask is harder to find than its predecessor (which would explain why Tarakudo and the Chans were always after the same mask) then Tohru (who only has a major role in episode 11) must've been struggling to locate the last mask for most of that time (maybe waiting for a potion to ferment or something during 'The Good Guys') and, since Tarakudo would've been happy to wait on the Chans, they had time to deal with Finnhalen, Drago, Chang and Daolon Wong whilst slowly locating that last mask.
This is corroborated by Ratso in 'The Good Guys' when he says they're on vacation. Clearly Tarakudo gave them vacation because they weren't needed for mask fetching *or* the world domination plan for after the masks are united!
Fridge Logic: Why was Jackie arrested in "Enter The Viper"? He wasn't caught inside the museum, nor was he caught with any stolen property. The cops just found him running down the sidewalk in front of the museum and slapped cuffs on him.
Because he was dressed like a cat burglar and fleeing the vicinity of a crime. Also, he did have stolen property: the Pink Puma gem.
Although he doesn't end up with the Pink Puma for long, after all Jade ended up with the gem. Which brings up another question, why did the police take him to jail if they discovered that he didn't have any stolen property on him?
Perhaps they felt that he was still an accessory to the crime itself. He did look like a burglar, maybe they felt that he was assisting in the crime, which is still a crime. If anything, they should have had him in for questioning only as he may know who did take the Pink Puma, but Jackie wouldn't tell the police it was Jade would he? They may have held him for "further questioning" after he refuses to give Jade's or Viper's names at the police station. That could explain why he stays in jail until Viper breaks him out.
Why is it so amazing when El Toro removes his mask during Fright Night Fight, and why do they hide his face in shadow when we already know what he looks like? His mask has come off more than once previous to this episode.
It was because this was being done by him himself, rather than another person. Plus it's to the drama for Paco, since El Toro did it to convince him to remove the oni mask. Paco idolizes lucha and would follow every tradition to the letter, so it was very crushing to see his hero willingly break the number one rule.
In Season 1, it's noted that, in the episode focusing on it, the Rat Talisman is the most important to regain for Shendu, as it will allow to escape his statue form, though he'll only return to full strength with all talismans. However, in the season 1 finale, he regains all talismans except for half of the Tiger talisman, yet despite having the Rat talisman, he doesn't escape his statue form. He only becomes animate again once the second half of the Tiger talisman is regained. Inconsistency?
It is tied to the power of the Tiger Talisman. It balances the other 11 talismans! So long as he lacks the complete Tiger Talisman, he can only use one talisman at a time.
Good guess, but actually, it was specifically stated that the spell that sealed him away required ALL the Talismans to break, which was why they were scattered across the Earth in the FIRST place!
While Dog Talisman is supposed to give the power of Immortality, it's been proven time and again that it also gives Nigh Invulnerability, of no damage taken variety. It's been shown consistently that while attacks can still hurt, no amount of deadly energy (proven when Moon Demon was attacking Dog-bearing Uncle in Book of Ages storyline) can give the person so much as a scratch.
And as one webcomic (unrelated) shows, the best keeping method for this kind of talisman is to swallow it whole.
As the last episode of season 1 and the first episode of season 2 show, the Dog doesn't TOTALLY eliminate pain and injuries (not to mention the episode that introduced it, where Uncle was knocked out while wearing it), pain and injuries are more Horse Talisman territory.
When Uncle trapped Daolong Wong's Dark Chi Warriors, Daolong Wong went and transformed Finn, Ratso, and Chow into his new Dark Chi Warriors. What if this is how he got his original Dark Chi Warriors? Even worse is the fact that he transformed Hak Foo who had no Dark Chi Warrior predecessor. Being able to transform Hak Foo implies that Daolong Wong can enslave everybody.