you have to unlock achievements
you cant without mods :(
you cant
complete all vidmaster achievements
No. There is no cheats or glitches to unlock anything in Halo 3. You cannot gamesave on Halo 3 either. Although there are no IN game glitches to unlock armor, you can use certain downloadable programs that can unlock the achievements for your gamertag which will inturn unlock the armour., however these are detected almost instantly and will result in a ban from Xbox Live. Many sites claim to have the ability to unlock all the armours, including the elusive Recon and Bungie armour, however such sites are scams and will simply steal your gamertag and/or email account. The only people with the power to unlock those armours are Bungie, the creators of Halo 3. Update: You can now also unlock Recon armour by earning (Or using the method I mentioned earlier) to get all the "Vidmaster" achievements over Halo 3 and Halo 3: ODST. You then go onto the Bungie website and you can unlock the armour for use ingame.
yes you can lose armour through halo it happens with patches and fix and i remember when everyone lost kantana and secruity armour you can also unlock armour for nothing through bugs hope this helps
The only way to get armor on ODST is to unlock it on campaign . Except recon wich you need Halo 3. By Mr. Happy Guy.
Captain
The most popular halo 3 armour is most likely the recon armour that you can get for your spartan by completing all the vidmaster achievements in halo 3 and halo 3 ODST. the least popular is the CQB armour, a.k.a the Close Quarters Battle armour
I'm sorry bud but there isn't a cheat code to unlock all the armour in Halo. PERIOD.
If you unlock 1000 gamerscore with those achievements then yes you can unlock the katana body Armour.