Halo/Stargate Fanfiction ideas. Request Help.

Hey there everyone. I’m thinking of doing a Halo/Stargate crossover on Fanfiction.net in the near future and I’m wondering does anyone have any potential ideas that I might use for inspiration. The fic is in the very early stages and I’m working on a basic plot. I’m trying to do a story where Ancient humanity from Halo end up in SG verse and in present come into conflct with the Tau’ri and the rest of the Milky Way. But I’m trying to figure out a justification for such a conflict. One of the ideas is that it has to between an an encounter/conflict between ancient humanity and a faction of Ancients in another galaxy(prob Andromeda) whom broke off from the main Ancients during the plague and this conflict sparks a later one with the Tau’ri. I’m trying to come up with reasons for them though I am toying with an idea for the Ancients which was inspired by one of the stargate novels though. Does anyone have any ideas?

I have build a Stargate map in Halo Reach once xD
But right now I have no idea what you should write… Maybe tomorrow…