Halo 3 gamer points are points that you get from completing a achievements in the game. This points are seen on your xbox live profile and are for bragging rights.
1000 gamerpoints gives you the katana, not the security armour.
Most map packs are 800 Gamerpoints and need to be purchased via XBOX LIVE. Sometimes, there are discs out there for sale, but I highly doubt there are any for Halo 3. There used to be for Halo 2 though. Bottom line: Purchase from XBOX LIVE for 800 Gamerpoints. (Except Cold Storage, that one is free!!!!)
get a 1000 gamerpoints and 49 achievements. alot of times it glitches and you get it before that. u just need to be close to a 1000 gamerscore points.
Getting the katana sword would mean you would have to unlock every achievement in the game. So you would need both the regular Halo 3 disk for the Campaign achievements and the mythic disk for the online and multiplayer achievements.
Completing missions in Campaign,playing online, the rest you can find out if you hold down the giant X button in the middle of the controller then going left until you see ''Acheivements'' and see Halo 3 Acheivements.
There are two ways to get the "Katana" sword in Halo 3: Get 1,000 Gamerpoints in Halo 3 or get 49 out of 79 achievements in Halo 3. I recommend that you finish campaign on Legenday first (so you already have a lot of gamerpoints. It is frustrating, but it is worth it.) Then, just play the Legendary and Mythic Map Pack and get the Achievements there (most are about 25Gs but some are 50Gs.) Good luck! You can Also get it by getting 50 EXP points in one playlist on Matchmaking (Online)
Unfortunately, gamerpoints can't be transferred from one account to another, even if you move the save file.
you gut some
Nope.
halo 3 obviously
Halo 3: ODST is the newest of the two, but not the newest Halo game.
The halo time line goes Halo Wars, Halo: Reach, Halo:CE (halo 1), Halo 2, Halo: ODST, Halo 3. Halo 3 and ODST are practically at the same time.