[Mustakrakish]

Hello everyone! 
I recently read Earthdawn 4e, and I decided that I want to run a campaign that will take the story from the 4th world (ED), to the 5th (I will use Call of Cthulhu rules, and it will be around WWII), to the 6th world (Shadowrun).

I would love to hear ideas how can I connect the three eras together. The players won't play the same characters, at each world we will have new heroes, but the main plot will continue until it's conclusion with Shadowrun!

Would love to hear your ideas!!! 

[Mustakrakish]

I am thinking maybe I can tie it up with the Dawn of the Artefacts missions from SR 4e.

[0B]

You taking all crazy ideas?

You could:

• Characters get stuck in an ultraviolet host without knowing. Turns out the UV host is part of the now-fractured memory of Eliohann, scattered across the matrix. Players have to figure out that they're in the UV host, and then figure out how to escape. They could try brute force to let him have peace once and for all, or they could try restoring the cracks in Eliohann's memory.
• Astral rifts (A la Slip Streams) cause "maybe" time travel to the past. Players can move to and from the past using strangely placed phone booths. Up to you if that's a Matrix reference or a Doctor Who reference.

[Mustakrakish]

You taking all crazy ideas?

You could:

• Characters get stuck in an ultraviolet host without knowing. Turns out the UV host is part of the now-fractured memory of Eliohann, scattered across the matrix. Players have to figure out that they're in the UV host, and then figure out how to escape. They could try brute force to let him have peace once and for all, or they could try restoring the cracks in Eliohann's memory.
• Astral rifts (A la Slip Streams) cause "maybe" time travel to the past. Players can move to and from the past using strangely placed phone booths. Up to you if that's a Matrix reference or a Doctor Who reference.

This is exactly what I was looking for. All of this lore treasures are amazing. Thanks!

My first idea was to create 3 different stories, with different characters but to connect it all somehow.
For example:
In the 4th world they maybe help to contain some artefact.
In the 5th world it's WWII and the bad guys find the location of the item, maybe with the aid of a mysterious immortal being from the previous mana cycle. And because the 5th world is mundane I thought about using Call of Cthulhu, sanity and all that jazz.
And then at the 6th world somehow conclude the story, now the players play as runners hired to something with this artefact.

I just don't know enough about Shadowrun lore I think.

[0B]

You taking all crazy ideas?

You could:

• Characters get stuck in an ultraviolet host without knowing. Turns out the UV host is part of the now-fractured memory of Eliohann, scattered across the matrix. Players have to figure out that they're in the UV host, and then figure out how to escape. They could try brute force to let him have peace once and for all, or they could try restoring the cracks in Eliohann's memory.
• Astral rifts (A la Slip Streams) cause "maybe" time travel to the past. Players can move to and from the past using strangely placed phone booths. Up to you if that's a Matrix reference or a Doctor Who reference.

This is exactly what I was looking for. All of this lore treasures are amazing. Thanks!

My first idea was to create 3 different stories, with different characters but to connect it all somehow.
For example:
In the 4th world they maybe help to contain some artefact.
In the 5th world it's WWII and the bad guys find the location of the item, maybe with the aid of a mysterious immortal being from the previous mana cycle. And because the 5th world is mundane I thought about using Call of Cthulhu, sanity and all that jazz.
And then at the 6th world somehow conclude the story, now the players play as runners hired to something with this artefact.

I just don't know enough about Shadowrun lore I think.

I wouldn't worry too much about the official lore. Some folks don't always like to admit it, but GMing SR isn't too different from GMing D&D: you can make up info about the setting on the fly. I never saw the point of sticking to a script in any TTRPG. If your players dislike what you do with the setting, they can tell you.

The nice thing about the slip streams stuff is that what you make doesn't even have to match up with lore. If there's a contradiction, that just creates a new hook: "why is history different in this rift?" You can avoid this sort of thing as well...