I don't think you can get it without a AR or trading so you would need the 493 master balls cheat.
How it works:You throw away a certain amount of them(Yes,you can get them back if you still have your AR) and when you throw the balls away,you have(hopefully) a Pokemon number.Then you go into wild grass and run around pressing L or R.(I forget which button because I haven't played my DS in a long time.But I know for sure it is L or R.)
action replay and stuff like that or you trade from the new Pokemon heart gold and soul silver
you migrate them. or you can use a action replay on it
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i don't know Damien seidler:
you have to migrate or trade in order to get a cyndaquil.
you cant do that you have to use action replay
Action Replay yourself a Master Ball.
You can't catch it in Pokemon Diamond or Pearl. You have to transfer it via Pal Park from Pokemon Emerald, Leaf Green, or Fire Red. Before you do this, however, you need to have a national Pokedex in both games, and have a Cyndaquil in the GBA game. This is somebody else. I know theres an action replay code to get cyndaquil in diamond becuz i have chikorita ad totodile.
You just need an action replay, but you can use either one.
action replay
with action replay codes you can catch any you like including mew and so forth
i did not catch deoxys without action replay it is really easy with action replay