The entire concept of having animals evolve into insanely-powerful beast monsters by beating the crap out of others in battle (or by being exposed to stones, being traded, etc.) is pretty ridiculous in and of itself. But it's not too difficult suspending your disbelief when the end result is a fire-breathing dragon who remains loyal to you (despite the fact you're forcing it to fight a bird who shoots lightning). But there are some specific evolutions that are extremely weird, even in the already-weird field of Pokemon evolutions. These are the 10 weirdest evolutions in Pokemon.
10. Cubone into Marowak
Cubone's life kinda sucks he's so upset at the death of his mother (remember, this is an entire species of Pokemon, meaning they all are bereaved over the deaths of each of their individual mothers), that he literally wears her skull, which may not be the most emotionally-healthy coping tactic. Then again, in some deeply, deeply messed up way, his mother is still protecting poor little Cubone since her skull now acts as his helmet. It's definitely indicative of some kind of creepy Norman Bates/Mother relationship, but it's mostly harmless.
Where it gets weird is when Cubone evolves into Marowak. Essentially, Marowak's just a bigger Cubone, which isn't all that weird. What is weird is that Marowak is defined by having gotten over the death of its mother (remember: AS A SPECIES, Marowaks have ALL gotten over the deaths of their individual mothers), but still wears a skull on its head. But it's specifically NOT its mother's! Meaning
Marowak found some random dead Pokemon's bigger skull and is wearing that now? Something tells me Marowak hasn't quite reached the closure it claims to have.
9. Fish That Turn Into Entirely Different Kinds of Fish
A lot of Pokemon have weird evolutions, where the following form bears little resemblance to the original. But, for whatever reason, this seems a lot more pronounced in a lot of fish Pokemon. Carvanha (a Pokemon resembling a piranha) evolves into Sharpedo (a Pokemon resembling a shark which is not a type of piranha). Maybe this was just a weird in-joke, since the film Piranha was a cheap rip-off of Jaws? What's weirder is Magikarp and Feebas, two fish Pokemon that look very similar, each evolve into things that are not really fish at all. Magikarp notably turns into a Chinese dragon-looking thing called Gyarados, and Feebas turns into some kind of majestic eel known as Milotic.
There are actually a lot more examples: Remoraid (which resembles a pet fish) turns into Octillery (an octopus). The normal Poliwag to Poliwrath evolution chain can take a total left turn and evolve into Politoed (which is a frog, instead of a weird blue thing with a spiral-patterned stomach). Clamperl (a clam/pearl combination, shockingly) turns into some type of eel, either Gorebyss or Huntail (depending what kind of item you make Clamperl hold onto). Then again, I don't know a whole lot about fish, so maybe clams turning into eels is the norm under the sea.
8. Baby Pokemon Who Just Start Hanging Out
Let's say you're hanging out with two friends. Fun, right? Oh, also one other thing: DID YOU REALIZE YOU JUST EVOLVED INTO A HIGHER LIFEFORM? Because you did. Well, at least according to the rules of Pokemon, where three Digletts equal one Dugtrio that can be treated as a single entity.