If you have an Action Replay for GBA, yes.
You cannot use action replay on gba games
Use Action Replay
Migrate From Pokemon FireRed,Or Pokemon LeafGreen,Or Use The Action Replay Pokemon Modifier.
No but if you own an Action Replay you can use codes to play as others
You have to trade it from ruby or use an action replay
No Deoxy is not in the grass but you can use a cheat with action replay or transfer him from Pokemon firered or leafgreen.
use action replay code. to do this, buy an action replay. if you already have this, use action replay code manager by using the internet cord it comes with. if you cant figure this out, go onto youtube and type this in and copy it on your ar. then there you go.
either use action replay or event or catch wild in victory road after you get mew.
You would use the game shard or the action replay depending on which version you have
Nowhere you must use action replay or gameshark to obtain that item.
You can never get Mew ever, that rumor has been going on for 11 years but you cannot get mew ever. Unless you use action replay
You will need a Action Replay(or it might be Gameshark) and you can find codes on Google.