For a franchise as huge as Pokémon, they often end up having a defining mascot that even those who have never experienced anything related to the brand know. Pikachu is that for Pokémon and over the last 20 years has become one of the world's most famous character and mascot.
The Pokémon Company has tried to capture the magic of the original electric rodent numerous times with little to no success or fanfare. Let's look at every evolution and knockoff wannabe clone of Pikachu and rank them from worst to first.
Let's first talk about the most uninspired and egregious Pikachu clone to ever exist. During the 6th generation of games, fans were introduced to Dedenne. This little thing may sport a secondary typing of fairy, but one look at it will have trainers wishing they were catching a Pikachu instead. Dedenne looks less like it's a unique Pokémon and more so like a weird counterfeit version of Pikachu you could get at an extreme discount. If it was on a shirt, it would likely have the name Pikachu slightly misspelled right below the image.
At the end of the day, both Plusle and Minun will also come across as colored versions of Pichu. It seems that the Pokémon Company had no shame when creating these two partner Pokémon. A neat mechanic they could have implemented is that the two would receive benefits for being in the party together. These are arguably two of the most blatant clones of Pikachu and its evolutionary line. Did they think that fans would fall in love with these little creatures sporting red and blue coloring alongside their negative and positive charges?
Togedemaru is the first of two Pokémon on this list, the other being Emolga, that could have easily had a more striking and unique identity, but were shoe-horned into the generational Pikachu-like role that a new Pokémon has had every generation since the Kanto region games. Togedemaru at least has the benefit of a steel secondary-typing which makes it feel like its own creature and its bulbous round body makes it a top-tier plushie candidate. It's just unfortunate it had to also include Pikachu's cheeks and tail design.
Unlike many of the other Pokémon on this list, Emolga easily has the most original body. It's similarities to Pikachu come in when you look at its coloring, face design, and the fact that it's an electric-typed rodent/small mammal.
Its inspiration seems to be that of a flying squirrel which is neat, but it's rather unfortunate that they couldn't stop themselves from making it look so similar to Pikachu. Instead of focusing on trying to give it a unique identity they relegated it to a creature most trainers overlooked and underappreciated due to its familiarity.
5 Alolan Raichu
It seems as though the introduction of Alolan Raichu was the Pokémon Company's way of trying to bring new life to a creature an entire generation ignored. Thanks to the anime there were very few trainers that evolved their Pikachu into a Raichu with the aid of a thunder stone. The Alolan form of Raichu not only gives the creature an adorable new look that turns its tail into its own personal surfboard but also gives it a secondary typing of psychic which makes it much more viable and useful in battle than its previous form, Pikachu.
Depending on who you ask the introduction of pre-evolutions, often referred to as baby Pokémon, was either the best or worst thing to happen to the franchise. Pichu was among the first batch of these things and introduced the world to a newer and arguably more adorable form of Pikachu. This little creature may not pack a punch in the world of Super Smash Bros., but it earns bonus points as it is a part of Pikachu's actual evolution line and not simply some wannabe clone trying to capture the magic of the franchise's mascot.
Morpeko is the latest of the Pikachu clones as it made its debut with the recent release of Pokémon Sword & Shield which introduced trainers to the Galar region. The reason it's this high on the list is likely due to the fact it's new which comes with a heaping spoonful of recency bias.
It does make a name for itself due to its unique ability called Hunger Switch which has it change between two forms every turn. One offers benefits for electric-type moves, whereas the other boosts the effects of dark-type moves.
The anime featuring Ash and his Pikachu was the worst thing that could have happened for Raichu. In its own right, it's a pretty cool electric-type pokémon that even the likes of Lt. Surge felt was capable enough to justify evolving your Pikachu. Ash forming a bond with his and never evolving it led to an entire generation of trainers who did the same and looked at Raichu as the lesser of the two. It's a real shame because an average Pikachu is nowhere as strong as a Raichu of the same level, but Ash's special partner created so much anti-Raichu propaganda.
The reason Mimikyu tops the list of Pikachu-related Pokémon is simply that it's not afraid to reference that it's biting on Pikachu's popularity and likability when it comes to the PokéDex and lore in general. This ghost-type pokémon simply wants to be liked as its natural form is frightening to anything that happens to catch a glimpse of it. Mimikyu knows how loved Pikachu is and simply wants the same thing. No one even knows what it looks like as the only person to have ever reportedly done so died shortly after of shock.
I out-tricked the trickster