[quote=@ErsatzEmpress]
Yeah Skrulls would be fine, but I'd like to refrain from having had a large secret-invasion scale event revolving around them prior to the start of the game. For clarity, if you want the FF to have faced Galactus off-world, or any of the other larger scale threats I have no problem with that at all. I don’t want to restrict your use of FF enemies, just trying to use common sense in terms of where we are as a game. It's not "Year One" but it's still season one.

If you would like to implement a Galactus style invasion at a later date, would love to discuss and coordinate that with you as that could be a fun cross-player event.
[/quote]

OK, I also agree that it's probably too early in the RP to bring alien threats directly to Earth's doorstep, so I'll say that one of the FF's prior missions was space exploration (a second attempt at Reed's experiment, which was to test a form of FTL propulsion) that sends them on a short trek through space where they encounter Skrull, Kree, and 'hear rumors' of the "Planet Eater".

Since returning, preparing Earth to stand strong on the galactic stage has been a constant nagging at the back of Mrs. Fantastic's mind. The FF have since fought off a few Skrull scouting parties, but nothing full-scale yet.