Pokemon Warp UltraMoon - I fused with Necrozma

First:  Epic Fusions Forever!

Though, you really need to work on your grammar. Or otherwise Past-present-future tenses. The phrases are a bit cheesy... Also you need work on perspection post-fusion. Since even when deliberately trying to keep memory's private they tend to mesh unintentionally, but your putting it like it is simply a power boast, one sided.
Which its not. I am assuming the palette from the gray skin and purple pants are from Hoopa's side of things? If not, considering its his pokemon half I think it would make more of a appearance. Is the capes inner lining of blue from Ellio?

On one hand, I can see that like this Soriel fusion: d.facdn.net/art/uberchargecovu…
It was a fusion made from trying circumstances. Or at least, one brought for the need for power. For instance, Sugilite. And I have the feeling that, like her, that single minded purpose may cause conflict. But then again, I only found these pokemon characters very recently.
On the other? I think you need to balance their combined idea of a strong warrior with who they are themselves a bit more. Even though we don't know the actual age of Necrozma. Ellio is technically only eleven despite what he goes though. That dual state would likely show itself, despite their wish otherwise.
Though, then again you saying he fused with "Yourself" So I might be talking about another person here. Please clarify.
How's their equanimity?
As a side note, do they use they/them pronouns?