Sooooo, this is an old fanfic so don blame or any thing for grammar errors (I'm not English )
«In another world»
Batman, when he gained his senses again, found himself lying on the floor of what seemed to be a garage. Hearing a noise, he turned and saw a man made of metal of red and yellow color pointing a hand at him.
"What happened?" Batman asked, half disoriented. This, he looked around and realized that he was not the only one present in the League: there his left was to Hawkgirl and there are right the Green Lantern lying on the ground; At some distance he could see a blue and red suit lying on top of one of the many cars present, just like the Wonder Woman.
"Don't move!" It was the answer the Iron Man gave him.
Across the room, a girl tried to get up - which proved to be a more difficult task than she thought.
"Tony, it's okay I ... - Supergirl!" Exclaimed the Spider-Man, just entering the gagarin, recognizing the blonde.
"You know these people?"Tony asked, continuing to point his hand at the man with the bat suit.
"The spider is an honorary member of the Justice League."Answered Batman.
"I wasn't talking to you." "As Stark said these words, the guy on the garage floor was losing his senses.
"Spider man?" She asked, half-dazed, to Supergirl.
Before Peter Parker could utter a word, the girl finally passed out.
What was unknown to the Avengers is the fact that Spider-Man has discovered a way to walk between the Justice League and the Avengers dimension using a portal. Through his travels, he eventually became an honorary member of the Justice League and fell in love with Kara.
When Supergirl passed out Tony and the rest of the avengers bring the leaguers to the most near hospital. After a few hours, after all the members of the League have been properly rescued, they finally wake up.
The first to question his location was Superman.
"Where am I? Who are you?"
"You're at the Santa Barbara hospital in New York." Pepper said quietly, rising from the chair where the last hour had passed."My name is Pepper. It seems Mr. Stark was experimenting with an inter-dimensional portal and eventually got you and your colleagues to stop here. Spider-Man explained to us that they were heroes, right now, we're doing all we can to make it safely back home."
But when the rest of the members eventually woke up, and after a very quick explanation and a few more questions, Pepper got everyone to wear their uniforms and into the limousine that would take them to the Stark Tower - also known as the Vengeance of the Avengers.