>>58578939Literally just Fire and Flying spam, Poison types and Poison moves are really rare in VGC, Ice spam isn't very common either. Mega Meganium is Charizard food and that's it's biggest issue, but it completely walls Koraidon and Miraidon's STABs, it destroys Urshifu, it deals with Rilaboom really well, it's bulky enough to eat fairly strong hits and it has reliable recovery and a pretty good new set of coverage moves to pair up with it's already fairly decent support moveset. It also survives Incineroar's Flare Blitz.
If Mega Meganium gets a good ability it's going to be at least decent and see a lot of experimentation, the second big issue with Mega Meganium isn't even that it's bad, but rather that it has such tough competition, Mega Venusaur completely and utterly destroys Primal Groudon and Kyogre, as well as generally not giving a shit about much due to how fat it is. Meganium just needs something to set it apart.