well, if you start a new game and save then you lose your old account, but, if you do NOT save on your new account then you can still play your old one
Because the battery is dead in the game preventing the game from saving.
Tap "New Game" and then save. You have started a new game and erased the old data. You will not lose your downloaded mission. Source: Experience
The Gender of your starting pokemon is on pure luck just keep restarting till it's female.
All you need to do to get shiny legendaries is save your game right before you fight a legendary and if it isn't shiny than just keep shutting your game off and turning it back on. This works for all versions starting with Pokemon Silver and Pokemon Gold
yes,you can
You Can keep playing the game but not with the Pokemon you migrated
Yes, you get to keep every one of your Pokemon on the game you transfer them from. It just copies the Pokemon to Battle Revolution, so you keep all of them on both games.
You cannot keep a pet Pokemon in Pokemon Emerald. Pokemon are considered your friends, and as such are placed in your party and cannot be kept as recognized pets in the game.
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yes, also you can keep trading Pokemon to the beaten game and keep restarting the other game so that your new game can have all three starter Pokemon
You have to press UP on the D-pad, and press the B button, and press the X button (UP + B + X all at the same time). Remember, if you start over, you will lose anything you had in your game, so if there are Pokemon you want to keep, trade them to a different game first.
In Animal Crossing: New Leaf, you can't delete specific save data directly in the game. However, you can remove save data by going to the Home Menu on your Nintendo 3DS, selecting the game, and choosing "Delete Save Data" in the game settings. Keep in mind that this will erase all your progress, so it's a good idea to back up any important data before proceeding. If you want to keep some data while deleting others, consider starting a new character on a different save file.