Go to the Pokemon center and in the PC select a Pokemon and click release
Chat with our AI personalities
Click new game at the menu
Either trade from a differnt game or cheats. Only way(s).
Technically,yes you can get Arceus in Pokemon Heartgold,but only by trading it to your Pokemon Heartgold game from Pokemon diamond,pearl or platinum.
First you delete your save game, edit the contents of the game chip... Just kidding! REAL ANSWER: you can't, sorry dude.
To delete a game file for any Pokemon game, you need to press Up on the control pad, then Select, then the B button. Hope I helped! it dont work if you want to delete in laptop first make a folder and keep all the pokemon game stuff in it the in that folder you will see a search bar on top right.In that search the game name like pearl, heartgold, etc. the you will see the related search there will be a blank page named as Pokemon pearl.dsv or ds1 and etc. and delete all the dsv and dsv and ds1, etc. and the name could be anything like Pokemon diamond.dsv or Pokemon heartgold.dsv. the will be the same as you write on the search bar. hope i helped.