Nightmare Fuel / Victor and Valentino

• The titular "Suerte" has characters that come to life and make other people take their place whenever someone cheats at the game. It happens to Victor, and it nearly happens to Valentino when El Colorado chases him around the house and corners him.
  El Colorado: Pobrecito. You pay the price for your brother's lie!
• The Collector. Seriously, don't watch this episode if you're afraid of dolls.
• The black cadejo in "Los Cadejos", which brainwashes Victor to attempt to get him to kill himself. Not only does the thing have a severe case of Red Eyes, Take Warning, but when it's found out by Valentino and a white cadejo trying to save them, it suddenly undergoes an extreme case of Body Horror worth of the Squick entry below by having parts of its flesh rot away to show bone beneath, as maggots just fall by the bucketload out of its body.
• The tree that turns Victor into a sapling and assimilates all his and Val's friends to the latter's treehouse. All this happened because Victor took one of the tree's branches and made it into a hat rack.
• El Silbon, a gaunt, undead-looking figure that uses whistles to remove victims' skeletons as casually as removing a coat from something, leaving them as still-living heaps of flesh.
• In "Welcome to the Underworld", Achi takes Victor and Val to the eponymous Underworld so the former can get wrestling advice from their late uncle. However, they are captured by the Bone Boys, who intend to keep them in the Underworld forever.
• La Planchata. She's the ghost of a nurse who's flatter than cardboard. The way she moves combined with the faces she makes along with how her eyes dilate is super creepy. Normally, she's a Friend to All Children, but she only heals those she deems worthy. Otherwise, do not get on her bad side. Just ask Victor, whom she threatened to iron flat!
• Everything to do with Tez. Or rather, Tezcatlipoca. He appears to be an affable magician and a Cool Old Guy, but turns out to be in league with the Tzitzimimes. Over the course of the show, he is revealed to have big plans for Monte Macabre, which involves a giant monster.
• Everything surrounding the Tzitzimimes! They are deities of darkness who seem to be the stars trapped in the night sky. Their true forms are these living blobs of stars with many faces. They will possess whoever looks up at the stars on certain nights or whoever seems to know of them. Whoever acts as their vessel will have twinkling stars in their eyes and begin acting strangely. And soon enough, start twisting and contorting in painful, nightmare-inducing ways! In their first appearance, one takes a hold of Don while Victor and Valentino try to get him mad with their pranks. What follows is such delightful imagery as Don breaking his teeth on a tin can, jump-scaring the boys from behind a freezer door, crawling around the walls and ceiling, squeezing under a door while his bones audibly crack and break, and when it exits Don's body, leaves him flat and deflated like a balloon! They later show up when the kids are camping and Isabella tells them the myth and they get possessed themselves and try to chase Vic and Val. The absolute worst moment is the terrifying grin Isabella gives when Val asks her if she's possessed!
  • And we find out in a later episode that these cosmic abominations can possess machines in the episode "Carmelita" when they possess the titular vehicle to try and kill the boys!
• The Mega Tzitzimime takes the cake. Their first major episodes "Another Don" and "Starry Eyes" start off as a standard mystery with Vic and Val trying to solve the mystery of who stole their grandma's water vessel, with Isabella tagging along. Isabella always points out suspects very quickly and at one point she points the finger at Don. We later see Don breaking into their house only for another Don to stop him. The brothers chase the other Don to a cave, filled with skin suits of everyone in town, they then see Isabella creepily dancing around a fire, only for her skin to tear open revealing large spider legs, then she tears off her skin and clothes to reveal a skeletal spider woman with eyes on her hands. The two are attacked by the creature only for it to escape into broad daylight. Xochi and Don join the brothers and reveal that the creature is contacting the other Tzitzimimes and the group start questioning if it disguised itself as one of their neighbors, with the group questioning if Isabella is the creature. Isabella's personal information is contradictory and some parts are flat-out lies, but she tries to distract Val from the mission with a date. Val and Isabella meet in the desert only for her to grow wings and try to carry Val off into the sky. The group show up fight the beast, at which point it reveals that the girl Val gave his heart to, was never real in the first place. And based on the design of the creature, it's implied to be the Queen of the Tzitzimimeh, Ītzpāpālōtl, a skeletal warrior goddess who ruled over the paradise world of Tamoanchan, the paradise of victims of infant mortality and often takes the form of an Orizaba silkmoth.
• Isabella's death is an incredibly painful and tragic moment. Despite being rejected by Valentino during the events of Star Child, she still returns to save his life in the season three finale. This time she is caught and her four insect legs are painfully ripped off by the Jaguar Patrol. Next Tez starts to open a portal into the night sky and starts to slowly shatter her like glass, all while she is fully conscious and completely aware of what is happening. He tries to make it as slow as possible, only speeding up the process when she uses the chance to tell Victor and Valentino how to defeat Tez. Valentino desperately reaches out to her but there is nothing he can do for her now. Before his eyes the process is sped up to silence her. Now the pain is so bad that tears run down her face as she says how happy she is that she got to meet Valentino. Finally she is fully broken apart and turned back into a star.

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