So when you think of large pieces of land, water comes to mind as a good representative? Water is like the opposite of land. Water would be the worst representative. Even worse than Electric and Poison.continents also ”contain” a lot of water through inland seas and groundwater by this logic, this argument sucks
By your logic, it would make more sense if Continental Crush was a Water move because mountains contain a lot of water. But obviously the mountain used in the move has the properties of rock, being solid and hard. It is not liquid like water. The target does not get wet from it. That it would contain a lot of water does not matter.
Steel, Rock, and Ice are the solid things of which continents are made which Regigigas would tie his ropes around and pull together. Water, Electricity, and Poison are not what people think of when they think of huge landmasses because huge landmasses are not wet, liquid, shocking (in literal sense), nor poisonous.
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There is more critique to be had concerning the Galar Regis.
The Regis stand for times. Ice Age, Stone Age, and Industrial Age. Regigigas made a Regi during each age of existence.
But in Galar 2 Regis were made at once, Regidraco and Regieleki. They are fake, and the times for which they stand are fake. Search through the history books as you might, there is no Dragon Age nor Electric Age.
The latter may seem like the Information Age to the naive, but Regieleki is not Information Type. Porygon is the virtual Pokémon, and he is Normal type. Thus Normal type is the Information type. Regigigas stands for the Information Age. Regieleki is a usurper king at best.
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More evidence of the Galar Regis being fake is the fact that the Galar Regis are pay2win.
The original Regis require intelligence, perseverance, and skill to get. Those Regis do not care for money, but they do demand you prove that you are worthy of them. Getting them is a true victory with a befitting reward.
But the new Regis do not put you to such a test. They do not even require the reading of Braille. Instead, they require money. You have to pay in order to get them. Getting them is not a victory of character, but a loss of finances. But at least the reward is still fitting: fake Regis for a fake achievement.