So me and my friends were doing a Pokemon DnD, and one of the enemies is supposed to have a Mega Rayquaza. I know we can just select the Mega Rayquaza right off the bat (custom format), but I want to know how do you mega evolve it in Showdown now. We have Dragon Ascent. What else are we missing?
You just have to be in gen 6 or gen 7 or national dex (AG) to use it. Just make it learn the move Dragon Ascent and you can mega evolve in Showdown.
Source: Experience