Water Pokemon are simply either too bulky or too strong to ignore in Pokemon GO.
Some of the most powerful Pokemon in the game (Kyogre, Palkia, etc.) share the Water typing. Not only do most of them drop loads of damage, but they also provide key resistances to popular types like Fire and Steel. Conversely, only a couple types of Pokemon can deal with them, making them a priority for any good team to account for.
Pokemon GO: How can trainers beat Water-type Pokemon?
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Water has two weaknesses in Pokemon: Electric and Grass. Dragon, however, also resists Water moves, making it a soft check to Water as well.
Either of these types work well, but in most instances, Electric-types will inflict the most damage. Typically, Electric-type Pokemon have high Attack stats and deadly weapons, whereas many Grass-types are more defensive.
If trainers consider the Raid counter rankings for Blastoise, they will notice most of the high rankings belong to Electric-types (Mega Manectric, Shadow Raikou, Shadow Electivire, etc.).
Shadow Tangrowth and Mega Venusaur rank at 7 and 8, respectively, but those are the only Grass-types to hit the top 10.
In terms of specific Electric-types, Mega Manectric is top of the line. Its 286 Attack stat is superior to many Pokemon, and he gets access to Wild Charge, one of the strongest 50% energy moves in the game.
Other considerations for Electric-type Pokemon would be Raikou, Zapdos, and Zekrom.
Due to their damage output, Electric-types are certainly better in Raids. In PvP, however, the best general check is Grass, since this type resists Water as well as hits back hard.
Many of the strong Electric-types are frail (Mega Manectric included), which means that they still need to stay healthy throughout the match. A low-health Raikou will still lose to a Kyogre if it has a charge move lined up.
Grass-types get to worry less, though. Pokemon like Venusaur can sit in front of Azumarill all day, since none of Azumarill’s attacks can hurt Venusaur.
Finally, potent Dragon-types can beat Water-type Pokemon without doing super effective damage. Since Dragons resist Water moves, they can farm up energy and charge their Draco Meteors and Outrages to pick up easy KOs.
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