The show was pretty light hearted compared to others, but it did have its moments.
- The Shadowkhan. Creepy humanoid demon warriors that are completely mute and can pop in and out of any shadows. In Season 4, we're introduced to new species of Shadowkhan that look even more monstrous.
- Daolon Wong may be one of the most hapless of the shows' Big Bads, but he has always had a certain hideousness in him. The other Big Bads are demons (if you discount Valmont), but Daolon Wong is a human (though his insides are apparently screeching dark spirits), and he starts in his every appearance a more serious tone than any other human villain. He's also all but confirmed to have killed Chi Master Fong. Plus, he can create in his palms fanged mouths to absorb energy from other beings.
- Tohru is close to cutting open Jade's stomach with a huge sword in order to get the Rooster Talisman from there. Jackie, who is handcuffed to a nearby pole, can do nothing but watch.
Project A, for Astral
- Jade ends up activating the power of the Sheep Talisman, which gives her Astral Projection. Unfortunately, the Dark Hand steals it and gives it to Shendu, who becomes a spirit and possesses Jade's body. Though Shendu is later exorcised, and Jade's back to normal by the end of the episode, the idea of being trapped in spiritual limbo forever while an evil spirit possesses your body is terrifying.
Day of the Dragon
- Shendu obtains all 12 Talismans and turns back into his true form, a mighty and intimidating dragon. When Valmont tries to confront Shendu over the treasure he promised, Shendu refuses to pay up, so Valmont orders Tohru to fight the big demon dragon. It goes as well as you'd expect, with Shendu using his telekinesis and super-strength to effortlessly throw Tohru out of the skyscraper. Though fortunately, Tohru survives the fall with just some broken bones.
- Of course, now Jackie has to stop the evil plans of Shendu, who is traveling to China with the goal of summoning an army of dragons to destroy all of Asia. Jackie has to defeat Shendu by carefully removing the Talismans from his body. Shendu comes close to killing Jackie, such as trying to eat him when he was unconscious, and eventually he grabs Jackie and prepares to toss him through the portal to greet his hungry dragon minions.
- One scene has Jackie climbing a bunch of vines to reach the Snake Talisman. However, they aren't really vines as Jackie finds out the hard way. And that's before the giant snake that even Tohru barely manages to hold off.
The Curse of El Chupacabra
- The titular Chupacabra scratches El Toro, causing him to become another hideous goat-eating monster every night. El Toro's transformation doesn't look pretty.
Queen of the Shadowkhan
- Jade places on herself the Mark of Tarakudo, which sticks as a tattoo. It gives her control over the Shadowkhan. At first it sounds cool, but she slowly becomes more bloodthirsty and demonic-looking. Finally, she has become blue-skinned and red-eyed like the Shadowkhan themselves. And her behavior until the tattoo is removed doesn't help either.
- Appropriately for an episode set in outer space, we get to see Tso Lan the Moon Demon; who resembles a tall and sinister space alien, and he looks and acts rather creepy, even for a Demon Sorcerer. And then there's his plan to use his gravity magic to disrupt the Moon's orbit, which would wreak havoc upon Earth's biosphere, because he'd prefer the world to look this way before he conquers it.
Into the Mouth of Evil
- Three criminals reveal their plan to use an ancient artifact to dry up the Ganges River, allowing them to reach the various treasures on the riverbed. A horrified Jackie points out that without the river, millions of people in India will die of thirst. The criminals are completely unfazed, and even laugh at him for caring about people while they will soon be filthy rich.
The New Atlantis
- After Bai Tza the Water Demon learns that San Francisco is in a potential earthquake/tsunami zone, she gets the idea to flood the whole city in order to replace the ruined Atlantis as her new undersea capital.
The Eighth Door
- While the Chans are chasing Bai Tza to banish her back to the Demon Netherworld, Jade accidentally gets caught in the spell, which sends her through the portal to the Netherworld as well. Jackie, Uncle, and Tohru have to race against the clock to rescue Jade, before the Demon Sorcerers get to her first.
- The Book of Ages-altered Earth where the Demon Sorcerers rule all. And of course, all humans have been enslaved. And if they displease their demonic masters, they will likely be tortured or killed (or maybe even eaten).
Chi of the Vampire
- Hak Foo, hamminess aside, was always an intimidating foe, but when he gets turned into a Dark Chi Warrior in Season 3, he had god-like power. In one instance, after Jackie and co. escape to a plane, he jumps a thousand feet into the air and lands on the wing of the plane.
Attack of the J-Clones
- Bartholomew Chang has an entire crew of clones of the J-Team members created. One of the clones sent to infiltrate the real J-Team is a copy of Paco. While the Paco-clone fights the heroes, its face gets removed, revealing that it actually lacks human facial features. Later they find and rescue the real Paco, who is trapped in a cage somewhere.
- Tarakudo's cries for help inside Alcatraz that lure in Captain Black sound downright creepy.
Fright Fight Night
- One of the creepier types of Shadowkhan are the Squid Khan summoned by an Oni-possessed Paco, during this Halloween special no less. These demons are well, somewhat squid-like and fight with long, stretchy tentacles. A security guard makes the mistake of unmasking one of them, revealing its hideous face.
The Shadow Eaters
- The Shadowkhan are scary enough, but a special mention goes to the Leech Khan. They initially appear as tiny and harmless, but their ability to eat shadows makes them more terrifying. They grow in size with every shadow they consume, eventually becoming able to eat whole humans.
- After Tohru's and Chow's shadows are eaten, they fall into comas, and they wake up from it only after their shadows are returned to them. How it would be like to be left in an eternal sleep?
J2: Rise of the Dragons
- The fire that targeted the Jades when they barely managed to escape the taxi cab looked pretty deadly. A split second after they leave, the cab explodes, forcing the girls to the ground.
- The fact that Future!Jackie and Future!Uncle are minutes away from certain death at the hands of Shendu if it wasn't for Present!Jade's quick thinking.
- After the Chans recover all the Oni Masks, this turns out to be a bad idea — uniting all of them causes the masks to break, freeing all the Oni Generals and their Shadowkhan. Tarakudo then launches his plan of having the Generals summon enough Shadowkhan to shroud the Earth in eternal darkness. Everything, not just the sky, would be shrouded by an endless veil of darkness, while demons overrun the world.
- Jade ends up getting a Foot-in-Mouth moment when Drago breaks out of the net Captain Black shot at him with ease. Her face says "I fucked up."
The Demon Beneath My Wings
- In-universe, Jade gets scared witless when she sees that her teacher Ms. Hartman has turned into the Sky Demon, and believes that she's become an evil monster. But fortunately, Hartman only uses her new powers to protect Jade from Drago.
- The old mansion that everyone visits turns out to really be haunted after all. Ghostly poltergeists possess the furniture and decorations, trying to attack anyone that gets close.
Weight and See
- Tohru's gradual transformation into a Mountain Demon. At one point while he's pigging out on food, we can see an inhuman tongue sticking out. Eventually he grows to a ginormous size and starts trying to devour anything within reach.
- The Chi Arcanum was something Shendu, his brethren, Daolon Wong, the Japanese demons or Drago had either never known about or had long forgetten about it. The arcanum's name means 'secret', so besides summoning a new type of Shadowkhan—one that's been never seen before—, there could've been a lot more Iso/Jimmy could've done hadn't it been for the Chan Clan and Section 13 stopping him.
The Powers That Be
- Drago finally obtains all 8 Demon Chis, allowing him to transform into a giant mix-and-match monster with traits of all the other Demon Sorcerers. He then empowers the Ice Crew with some extra Demon Chi, and they go on a rampage through San Francisco, leaving a decent amount of destruction in their path.
- The Ice Crew break into Section 13 and trash the whole place. Tohru orders Jade to escape, while the walls collapse around Tohru and apparently kill him. It's a good thing that he only later turns out to have been knocked unconscious.