Howard Mackie does something in the beginning of the Mutant X Series that I found a really great writing trick. We never really have a clear chance to settle into the time that is occurring. We read about Havok entering this strange new world and come to the close of that moment and when we rejoin Havok in the next issue we are smack dab in the middle of the next adventure with no setup. It helps to simulate for the reader the same emotions Havok himself is feeling.
It is nice to say good things about Howard Mackie after watching him saddled with the convoluted Spider-Man Clone Saga. Here he gets to take the Marvel toys and really shake up the sandbox. In Issue #2 we are introduced to the Mutant X version of the Fantastic Four. The story opens with The Six flying to answer a distress call from the FF concerning an invasion from a so called alien dimension. Havok is not only unsettled as he is now leading a team that is the world's best super heroic team, so he will be facing the misdeeds of his counter-part of this alternate Earth. See, apparently He and Sue Richards had an affair. It is an implied thing as we meet the FF and watch the two teams battle.
Break down on this Fantastic Four is as follows; Reed is still a genius and wears an armored suit with detachable extra arms, Sue wears a Stealth suit, Johnny is in a suit that lets him fly and throw fire, and Ben is still human and wears a big hulking armor with a terrible face. Reed is very off putting and later in the series we will see why. Sue seems glad to see Havok, while Maddie is not happy to see them together.
The rest of the story is a set up to get us to the nature of Havok as a traveller from another Earth. The resolution of that end of the story has a shock. As for the villain, he was strange. A small mentally powerful bug named Moot. Thing is he almost took over the FF and then Havok. So this starts the fun adventures of The Six and our alternate reality displaced Havok.