It appears that Niantic has been paying attention to the Pokemon GO meta, and seeks to now balance it– or at least mix things up.
Up until this point, certain Pokemon— Dragonite, Snorlax, Lapras, Vaporeon– have been demonstrably better for gym battling, due to their potential maximum Combat Power rating. CP takes into account a Pokemon’s health, attack power, defensive power, and ability to attack quickly and effectively.
A good example: Snorlax’s Lick attack does very little damage, but can be used much quicker than most moves, and prepares his “charge attacks” quicker than most other Pokemon. This, coupled with his overall high stats, makes him a favorite. Developer Niantic has tried to fix balance issues in Pokemon GO before, to limited success: Moves were rebalanced at one point, for instance, but this wasn’t enough to knock the “kings” from their thrones in terms of meta ranking.
Niantic seems to be taking this rebalancing more seriously now by tackling the Pokemon’s CPs directly. In a statement, Niantic explained that they’ve “made adjustments to the CP (Combat Power) of various Pokémon. Some Pokémon, such as Alakazam, Rhydon, and Gengar will have their CP increased. Others will have their CP lowered. These changes will allow a more balanced and competitive battling and training experience in Gyms. We will continue to adjust the CP going forward to improve the game balance when necessary.”
It is noteworthy that they have boosted the CP of some of the game’s most difficult to acquire Pokemon (Alakazam’s first evolution, Abra, has a 99% run rate, for instance), which will incentivize players to actually try for these difficult Pokemon for reasons other than Pokedex completion. Perhaps trainers will have another reason to try out this week’s Thanksgiving event, which doubles XP and Stardust prizes for one week.