The Multiverse React To Each Other's Universe and Battles

Prologue

Somewhere in a space-like world, there is no building, no people, and no land, nothing is there except it is space. Nobody lives nor stays here for a long time.

Until now...

The entire portal appears on the ceiling as many people from other universes are getting dropped on the ground. After that, the portal disappeared. Many of them are groaning as they got hit on the floor very hard, while some are fine as they didn't get hit on the floor. They begin to stand up on their feet.

Michael "Mike" Wheeler: Ugh! What happened? Where am I? 

And then he turned his head to other people except for his friends he had never seen before.

Michael "Mike" Wheeler: Whoa... I didn't see you guys there.

Marta Lualdi: Oww... That hurt! Emil, are you ok?

Emil Castagnier: Yeah, I don't even know what happened.

Touta Konoe: Ugh! My back hurts, but I am fine, as long as I am immortal.

Solid Snake: Otacon, this is Snake, can you read me? Otacon?

Otacon (Metal Gear): Otacon here. Where am I?

Solid Snake: I was gonna say the same thing.

Then everyone saw each other who they never met before. Most of them are standing and doing nothing, while some of them are glaring and preparing for a fighting stance. The others are pointing their weapons and magic at each other without knowing who they were, or they are seeing some people who aren't human. They are in a standoff.

Yue (Arifureta): Who are you? Are you gonna attack Hajime?!

Artyom (Metro 2033): Я спрошу тебя о том же, малышка. Кто ты, черт возьми? (I'm gonna ask you the same thing, little girl. Who the hell are you?)

He said in russian as he aims his Kalash at Yue. She got confused at what he just said since she doesn't understand Russian.

Nagumo Hajime: What are you saying? Are you trying to kill my lover?

Artyom (Metro 2033): КАКИЕ?! (WHAT?!)

Doom Slayer (pointing a BFG9000 at Kisara): What... are you... doing here... demon? Are you... trying to... kill me? If you are... then... I'll... rip and tear!

Kisara (Engage Kiss): Are you threatening me? Who do you think you are?

Meanwhile, with AVALANCHE and some girls from Class 3-A.

Yue Ayase: Who are you guys? You are all weirdos to me.

Yuffie Kisaragi: Don't call us that, brat! You know nothing about us!

Nodoka Miyazaki: Umm... Girls, I think we should...

Haruna Saotome: Oohhh! A dog!

Red XIII: What are you looking at, humans?

He said as some girls from Class 3-A jumped a bit as this dog just talked to them.

Haruna Saotome: Cool! It talks!

Kazumi Asakura: This can be my scoop for my newspapers!

She said as she held her camera snapping a photo at them.

Ku Fei: Hey you! (she points at Tifa) Wanna fight me?!

Tifa Lockhart: Why do I want to fight a child like you? I'm not gonna fight children.

Meanwhile, Asuna, Naru, and Motoko are glaring at Cloud.

Asuna Kagurazaka: Who the heck are you?! Tell me or I'll just have to beat you!