Your starter, an arceus, which is optional if u cant cheat/heatran that knows magma storm, a staraptor or pigeot that knows fly, a ho oh or lugia, a giritina and deoxes.
Any Legendary at LVL 100.
The best sites to get AR codes are:CodejunkiesNeoseekerSupercheatsDsactioncode.com
Google "master code Pokemon pearl ar" and you should get some results Google "master code Pokemon pearl ar" and you should get some results Google "master code Pokemon pearl ar" and you should get some results
Sadly no, Nintendo tried its best to stop all the use of AR on Pokemon Platinum. But hackers found out how to crack the game. But their are many codes out there for Pokemon Platinum that are similar to Pokemon Pearl. You just have to look on the AR website.
Action Replay
Pokemon Pearl's game ID is APAE-31D0AFDE.
Pokemon RULES
you cant
no
Only with AR you can
The only way to get Celebi on Pokemon Pearl without AR cheats is via event distributions. However these events are no longer being held or supported for Pokemon Diamond, Pearl and Platinum.
Here are some Pokemon cheats for pearl: Rebattle