The Dreaded TCG Category
This famously quirky Creatures Inc. employee has his own trainer card, albeit one with no intrinsic benefits whatsoever.
Imakuni?
The final boss of Pokemon Legends Z-A: Prism Tower itself!
Hyperrogue Ange Floette
Hydreigon
Hydreigon may be a combination of hydra, drei (German for three), and dragon.
Pokemon Gold and Silver are the games we know the most about the development of, primarily thanks to a beta originating from this trade show.
Nintendo Space World
Pokemon Special is infamous for its surprising amount of violence, with the earliest example being Charmeleon's vicious attack on this Pokemon.
Arbok
Shiny Pokemon have made various appearances throughout the TCG's life, with different interpretations on what effects being Shiny has on play. This rule is the only one that's recurred through multiple incarnations.
You can only have one per deck.
Five actual literal vehicles powered by Revavroom.
Starmobile
Krabby
Krabby may be a combination of crab and crabby (grouchy or ill-tempered).
Diamond and Pearl were the source of several unused items that continued to be programmed into games up through at least Sun and Moon, but these three have never seen use in any context. (Name one!)
Seal Bag OR Rule Book OR Loot Sack
It's clear in the writing style that Special took several inspirations from this seminal shonen manga series, including multiple direct references throughout the early arcs.
Jojo's Bizarre Adventure
The limited type chart in the TCG means some types have to be compressed. Poison has been represented by these three types.
Grass, Psychic, Darkness
The final boss of the oft-maligned third (fourth, technically) Pokemon Mystery Dungeon game, comprised of the negative emotions of all Pokemon.
The Bittercold
Pheromosa
Pheromosa may be a combination of pheromone and hermosa (Spanish for beautiful) or formosa (Italian for shapely; Portuguese for beautiful).
Black and White's final TM was originally meant to be a distribution in HeartGold and SoulSilver, obtained by sending this item through the Relocator.
Lock Capsule
Much of the conflict between Yellow and Lance throughout the second arc is sourced from both of them being blessed by the Viridian Forest, granting them a telepathic connection to Pokemon and the ability to heal them. However, a third important character also is stated to have received these gifts, even if he doesn't show it.
Giovanni
This infamously expensive set was the first time ever Eevee and all eight of its evolutions were available in the same booster pack.
The final boss of Rumble Blast, and likely a familiar frustration to anyone who works with iron.
Dark Rust
Zoroark
Zoroark may be a combination of zorro (Spanish for fox) and dark, 悪 aku (evil), or arch- (prefix for "top" or "chief").
Game Freak had to issue a public apology after pre-release material for Omega Ruby and Alpha Sapphire showed Blaziken using this illegal move.
Ice Punch
Many characters in the early chapters are altered to villainous roles, due to a lack of available options in the source material. Most notably, this unassuming gym leader is made the overarching villain of the entire third arc.
Pryce
The TCG's selection of status conditions mostly matches the real games, but Delta Species brought these two unique conditions that have never been seen since. (Points go to naming either one)
Imprisoned OR Shock-wave.
The only legal TCG card that is considered a Pokemon, but is absolutely and inarguably not a Pokemon.
Koko
Forretress
Forretress and Foretos may be a combination of forest, fortress, and possibly ferro (Portuguese for steel) and turret.
This ribbon is programmed into Scarlet and Violet, and official material suggests it is intended to be obtainable, but it's not. Thank God for that, because otherwise getting every ribbon on a Pokemon would be nearly impossible!
Once in a Lifetime Ribbon
Ruby holds many secrets throughout the fourth chapter; primarily his Pokemon's levels are obfuscated, due to displaying their contest stats between chapters instead. However, his biggest secret, only foreshadowed by never holding six Pokemon at once, is his ownership of this infamous deus ex machina.
Celebi