Across the Continuum is a bit like the old scifi Sliders and Teen Titans combined
It all started with a beautiful blonde as do all Epic Myths this side of the world.
Emily Rodgers was called by her Uncle Nick (No relation) Fury as a cadet agent because he and SHIELD was swamped in securing a lot of Alien tech the Avengers and Xmen had left strewn across half the Tristate area. The teams were down and she was well a hero of last resort
The Mission caught a strange caravan of AIM (Applied Idea Mechanics) trying to move treasures they'd stole, captured, found, or made to a safer location
AIM an organization of intelligent criminals weren't caught completely surprised or unable to put up a resistance against even Emily and fought back
Emily and her shield managed to turn the battle but in the end her unit was down to 45% but everyone was breathing Victory all but a fat lady's warm up away was soured when one of the armored sky cars that had gone down began to glow and hum.
Emily judged the situation to be bad and ordered a bugout for one and all as she charged the smoldering craft
She was hoping she might understand or be close enough to be talked through any procedure to take care of the source of energy that made her hair stand up as she got closer.
What she saw when she got there was an odd chrome sphere that was smiling at her as it hovered over and odd case that lay open under it covered in strange runes reminding of her arcane powers study that taught her that magic was real. Logic said that it couldn't hurt to get it back in the box and close the thing back up and see if it quiets down but while she pondered logic and action in that half second the smiling sphere swallowed her left wrist and was invading her collapsed shields structure.
Then Blink and the Blonde and all the things within 20 feet were swallowed up by the energy now contained in Emily's shield
She appeared in a more primitive North America around the same level of tech as the 17th century except they had an advanced understating of medicine but her shield's inboard computer confirmed was the same stellar cycle she'd left. There she met a different society of humanity their medical advancement caused by a world wide plague. They were the 6th generation since that horror's end but passing through it made humanity more tolerant so the finding of the native North Americans was going much nicer than her former world
Her second journey was to an Earth of the future one that had experienced a surge of the talented and used their abilities to enforce a one world government where to Rule you had to have powers. She was accepted quickly by the rulers of Earth 2 as Emily called it and they had been all smiles till she discovered why, they wanted her body. They had discovered in her blood something they couldn't reproduce, the serum and that they had run models on her genetic code and discovered she could increase the number of Primary Elementals (Superman, Magneto, Hulk) by the number of children she could have in her lifespan.
She skedaddled out of there as soon as she could get the rather uncooperative energy entity that had settled into her shield to open another gate
Presently on Earth 11, your Earth Emily tries to enjoy life while discreetly researching what the hell is in her shield and how can she get home or even if
That's where the story starts and it can be in a DC world, Marvel world, or of your imagining
The siege is one of those objects that has its true origins hidden in rumor and objects that are similar to it and deserving of the title. All these devices share one common ability and that is to create a bridge across the Continuum connecting know and unknown alternate realities.
This particular Siege Perilous we will call the M Siege showing its connections to Emily.
The M Siege has been partly explained to Emily and this is what she knows.
1: This Siege has a spirit and it emanates affection for Emily and means her no harm.
2: This Siege is able to alter those that pass through it but choses to make everyone Emily”s age or near it (17-21)
3: This Siege is a Second Chance Siege and is attracted to people who regret their lives and exists to grant second chances.
4: This Siege wants to be with Emily but gives no reason why and to accomplish its goal the device will gate from wherever it is to her left wrist
This is all adaptable and open for suggestions and input