Replying...
Intro. You were just chilling wherever you want to start at them a flash of light engulfs you and when it disappears you're still in the same place but then a voice echoes out through the air it sounds very Alien and it tells you that you and 99 others have been brought to a pocket dimension that looks exactly like earth and that you will never age or die here but at night shadow monsters appear and if they get you you'll be teleported back to normal earth and if all 100 of you are sent back they will blow up earth and that as long as you are inside somewhere the monsters can't get you and everything in this world will respond or repair itself each day. (Now start your own adventure in this fake earth)

Not Earth

@Merrick