I like to mess around with custom YGO cards sometimes, and recently I had an idea for a Pendulum archetype. Working name: "Paranosis", an admittedly straight forward portmanteau of "Parasite" and "Hypnosis". The gameplay gimmick is giving the opponent Pendulum Scales that have negative effects for their controller. For lore, all the monsters are Normal Monsters who were corrupted in some shape or form, making them vulnerable to a parasite that targets the mind. They retain their ATK/DEF and Attribute, but their Types have changed to Insect (the parasite's Type) and their names are just "Paranosis [Type prior to infection]". Their identities and memories are being slowly erased and they become more (self-)destructive due to the parasite's influence. Currently I have four Pendulum Monsters, two Traps, and two Spells. The effects can be read in the attached images, but I'll briefly discuss why I chose the four monsters I did.
Warrior Dai Grepher:
He has the Dark Grepher and Dark Lucius timelines where he clearly was not okay. His rivalry with Warrior Lady of the Wasteland (aka D.D. Warrior Lady) is also at play, specifically insecurities regarding the numerous chaotic things that have happened in their battles.
Gogiga Gagagigo:
His first released card is Gagagigo and his youngest version is Gigobyte. The flavor text of each Normal Monster that portrays his life talks about his dark destiny and how he basically loses his own soul by the end. However, he also has close connections Eria, the Water Charmer and Marauding Captain. I focus on the former since he first partnered with her when he was young, but I might adjust the flavor text to account for the latter since that's the one his Gagagigo self most commonly interacted with.
Dragon Core Hexer:
Original the monster Dragon Horn Hunter, constant exposure to dragon's blood in her hunts have corrupted her in body and soul. She wasn't even able to save her village, which was destroyed without her ever realizing. So yeah, gal's going through it (and she's also my favorite Normal Monster altogether so I had to include her).
Dunames Dark Witch (Dunamis Valkyria in the OCG):
While Grepher clearly appears sinister in his Dark persona, the Dark version of Vakyria (the constant of her name in all other versions and what I'll refer to as henceforth) isn't as evil looking. She also doesn't have an Even Eviler Form™ ala Dark Lucius. But I went with her cause it allowed me to have two Level 4s (Valkyria and Grepher) and two Level 8s (Gagagigo and Hexer) that were all different Attributes and Types (which is important for the naming scheme and flavor). Plus I think someone who is a bit more courageous than the others allows for some spicy flavor text.
Please excuse the lack of placeholder images for the last three cards, but I wasn't sure what to use and didn't wanna get bogged down. The monsters are just the arts from their Normal Monster versions I'm referencing. If these had proper unique art, they would all be somewhere full of variable mixtures of fear and anxiety-induced rage (plus something indicating that an insect is influencing and blinding them to amplify their fear). Pervading Paranosis uses cropped art from Array of Revealing Light.