I don’t know what the acronyms stand for but users use them all the time.
Pleaselog inorregisterto add a comment.
These are all competitive tiers and formats. All of these tiers and formats have different rules and different sets of Pokemon you are allowed to use.
The tier system is different, however, and completely fan-made. They vary in Pokemon viability, and are essentially just a way to rank the usability of Pokemon.
AG should also be mentioned, another incredibly popular format that stands for “Anything Goes”. In this format, you can use any Pokemon from any tier, and you can even use multiple of the same Pokemon.
Long story short, other than VGC, they’re just a bunch of unofficial tiers and competitive formats.
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