Charizard

In Doubles OU, while Mega Charizard Y is one of the top three Mega Pokemon and is one of the best Pokemon in the metagame period, Mega Charizard X serves as more of a niche option and needs heavy team support to work at its best. One of Mega Charizard Y's key selling points is Drought, which gives it excellent utility as a weather setter and, more importantly, complements its already powerful Special Attack by providing a 50% damage boost to its Fire-type moves, which lets its Heat Wave take huge chunks of HP out of any opposing Pokemon that does not resist it. What Mega Charizard X brings to the table is the fact that it is a physical setup sweeper that is immune to burns, though its typing is also very useful, as it reduces Charizard's 4x Rock-type weakness to a 2x weakness, removes its Electric- and Water-type weaknesses (though Drought reduces the Water-type weakness on Mega Charizard Y as well), and gives it a neutrality to Fairy despite it being a Dragon-type. Mega Charizard X also has a very useful surprise factor, as opponents may find their typical Charizard counters, such as Electric-types, ineffective against Mega Charizard X. However, Charizard does have its share of problems, notably its middling Speed when compared to threats such as Mega Diancie and Mega Metagross. Mega Diancie in particular is common and powerful, which forces Charizard teams to play extra carefully. Charizard also has weaknesses to a few common offensive types, with Mega Charizard Y being weak to Electric-, Rock-, and Water-type moves and Mega Charizard X being weak to Rock-, Dragon-, and Ground-type moves. In addition, Charizard does not take neutral hits particularly well, meaning that you have to be careful when bringing Charizard on to the field. Mega Charizard X also has the unfortunate issue of having its best attack, Flare Blitz, wear it down quickly due to recoil.