It means that you are cheating
This depends on what you mean. If you mean they are creating entirely new Pokemon from scratch, that's hacking the game and I've never tried that. If you mean that they are modifying existing Pokemon (for example, having Thunderbolt as a move for Magikarp), then they are using a program known as PokeSav, which makes AR codes based on what you wish for your Pokemon to have.
And what game would you be talking about? if youre talking bout the Bourne game, you mean Jason Bourne.
I assume you mean jirachi. Jirachi is an event pokemon and is no longer obtainable in the U.S. through any means other than hacking.
Do you mean by hacking or Just playing.I don't think you can... Sorry... ANYWAY, Unless some one can correct me XD
Do you mean keledo if so its an event only Pokemon if youre talking about someother pokmeon let me know.
If you mean using an external device such as Action Replay then there are no consequences unless you are planning to enter any official tournament. They have ways of checking to see if your game has been altered in ANY WAY (even if you only used it to get an item) and you will be disqualified. Hacking roms there is no consequences unless you finish your game and try to sell it that's illegal i do not know thw punishment though.
Without cheating or hacking, battle heaps, and I mean heaps!
By new Pokemon do you mean starting a new game. You just start a new game them.
If you mean a game that has Pokemon in it but isn't strictly a Pokemon game, there's the Super Smash Brothers games. I believe that's it.
In the sinnoh dex it is dialga but if you mean after you beat the game it is Mewtwo
The routes in Pokemon game are a number to tell you where you are and how to get there.
The legality of "hacking" an online game depends on what you mean by "hacking".In the most common use of the term - it is illegal to hack an online game. In order to hack an online game, you are usually hacking the server that hosts the game. This is breaking and entering into a server that does not belong to you.If you are using cheat codes - that may not be illegal.If you alter the code, that's the kind of illegal hacking mentioned above.If you have legal access to the code - for instance if it is an open source community owned game, you may be able to legally "hack" it and modify it.