Question

Can mega gengar Gigantamax?

Answer 1

Mega Gengar cannot Gigantamax as Megas and Dynamax have not ever existed in the same games.

Though for something like NatDex on Showdown!... that’s actually kind of a good question. I would think it wouldn’t, even if they ever existed in the same game (but I doubt they will) as this would be too overpowered, plus the Dynamax button and the Mega button (and Z-Power too, but that’s not important here) are pretty much on the same spot.

Comments

Just so you know, the National Dex subforum on Smogon has a thread that explicitly says Pokemon can't Dynamax if they hold a mega stone. https://www.smogon.com/forums/threads/national-dex-mechanics-thread.3656786/

Answer 2

Mega Evolution is unavailable in Pokémon Sword and Shield, due to the lack of Key Stones and Mega Stones.

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Gigantamax (Japanese: キョダイマックス Kyodaimax) is a special kind of Dynamax introduced in Generation VIII.

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The eighth generation (Japanese: 第八世代 eighth generation) of Pokémon games is the eighth installment of the Pokémon video game series. The eighth generation began with Pokémon Sword and Shield

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Therefore, it's not possible to mega evolve and gigantamax any Pokemon in a game.

Comments

Oh look, I got sniped.