Does ultra necrozma count as a mega or just another form?

Question

Is ultra necrozma a new mega form or just a form that activates when the ultranecrozmanium-z activates (I need to know because I am planning to add mega mewtwo x and zygarde to a team and I do not have the game yet)? Thanks in advance.

Answer 1

Ultra Necrozma is not a mega Pokémon.

It's a transformation called Ultra Burst, introduced in Ultra Sun and Ultra Moon. To undergo Ultra Burst, it must meet the following conditions;

1. Be in either Dusk Mane or Dawn Wings form, which is when Necrozma fuses with Solgaleo or Lunala respectively.
2. Be holding the Ultranecrozium Z.

Additionally, one turn after Ultra Burst has been activated Necrozma can use it's exclusive Z-Move “Light That Burns The Sky' as long as it knows Photon Geyser

Source: https://m.bulbapedia.bulbagarden.net/wiki/Ultra_Burst