You can play invincibly, but you have to beat the game on normal mode -and- you have to beat all of the challenges of the gods and unlock the combat arena. In the combat arena, select infinite health, magic and special, select a gaggle of gorgons and die by jumping while stoned repeatedly until the game asks you if you want to play in easy mode. Choose no, and load a new game. Your new game will enable you infinite health, and all your weapons will be available and maxed out. Be careful though, using the cestus to break things that you shouldn't be able to break yet will ruin your game. (This is a really easy way to earn the platinum trophy's hardest gold trophies: aMAZEd, and beating titan mode. Select "titan mode" when you are in the combat arena and you will have invincibility during your playthrough of the titan mode game.)

You can find a Halo 3 custome at Meijer. Or at Target

Throw a grenade and jump right above it as it explodes. If you don't jump high enough, damages can range from a full shield depletion to death. Plasma grenades will not be as helpful as they stick to any object and do not produce much of an explosion as frags. Finally, do not ever use spike grenades as the spikes will get you.

To get the security helmet you need to have over 1000 gamer scorer from halo and 50 achievements.

you can only create halo 3 levels on forge, which arent really levels at all

if u want to save your progress because a hardrive saves your progress through out the game

If you are feeling suicidal today, just pick up a spartan laser or rocket launcher and aim at the ground. You could also do this with four shots from a brute shot. Or if you want to get creative, shoot a couple fusion coils or plasma batteries. Anything that blows up can kill you in Halo 3.

i found it on a legit map only wich i think is the only way

The maps on Halo 3 are:

Regular Map Pack

Construct

Epitaph

Guardian

High Ground

Isolation (not in Matchmaking anymore)

Last Resort

Narrows

Sandtrap

Snowbound

The Pit

Valhalla

Heroic Map Pack

Foundry

Rat's Nest

Standoff

Legendary Map Pack

Avalanche

Blackout

Ghost Town

Mythic Map Pack

Assembly

Citadel

Heretic

Longshore

Orbital

Sandbox

Standalone

Cold Storage

Of these, some have multiple variants used in Matchmaking games such as Infection, Grifball, and others.

This occurs under 2 circumstances:

One is when you turn on your Xbox and go straight to halo 3 matchmaking it often will start off saying players failed to Load Content. The cure for this is to change to either a custom games or a forge lobby and chose a different map that came on one of the Map Packs. Then just go back to the lobby.

If that doesn't work then it simply means you haven't downloaded the Map Packs.

== == There are the skulls, but they don't really count as cheats, they make the game more interesting or harder (press X in the campaign lobby to turn skulls on, if you have found any) == == there is also a way to lower your weapon but i dont know how

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)

Go to Halopedian.com and look up the Great Schism. It explains in full detail. If you want the short version, here it is.

For thousands of years, the Prophets relied on the Elites for Protection and military strength. Then the Prophets betrayed the Elites by replacing them with the Brutes.

That's why when you play Halo 3: ODST you'll never see an Elite. Because the Elites were aligned with the UNSC during that conflict.

Also, the Elites and Brutes have had a long history of conflict. The next time you play Halo Reach, notice the groups that attack during campaign and firefight. You'll never see a group of Brutes and Elites together. Only groups of Elites or groups of Brutes.

This makes no sense. Anyway, if you mean how much can you do. There's 5 things to do. First, there's campaign(story mode) where you fight the covenant. Then, there's matchmaking where you have competitive games against people around the world through the internet that are set up by the Bungie (the makers of the game). Then, there's custom games this is like matchmaking but you set up the game and invite people to play. There is forge where you pick maps from the game, build stuff in them, and save them. Then, you can play on your maps in custom games. Last, there is theater where you can watch videos of your previous games. You can take pictures and record clips in them.

i think so i dont know if you have xbox live ask someone named redx56

go to http://sharesend.com/1tcny Download, save, open, click OK, go to xbox.com and sign in. Easy!

If you mean make unlimited armor lock, it's only possible in forge. you have to put out two armor locks, get one person in monitor, the grab one of the armor locks, use it and have the person in monitor delete all of them through the other one while your in armor lock. then you can walk around as normal except your invincible.

The Halo time period takes place starting in 2498 and ending in March 3 2553.

halo 3 is planned to come out for PC but there is no selected date for its release.

Halo 3 is to be released at this current year - 2010 and somewhere in fall or autumn September, October or November

use a tube corner to fly there blocking the towers beams then when you get close enough get a sheald and put it next to the tube corner then go back into human mode and there you go that's the sandbox skull for you.

[location:look at the sunset.you should see a tower next to it and theres a other tower on the right to it. in the middle beatween both towers there should be a ditch in the sand and that's were the skull is.]

p.s ENJOY!

well all you have to do is go into custom game or forge go into options and then go into weapons and damage then put weapon ammo on unlimited but if you want unlimited ammo in campain you cant unless you hack wich is illeagal and should'nt do cause its bad or u get a really good glitch

Normal, heroic, or legendary. I found a two skulls on easy, but I didn't get an achievement.

kino comes by default which means its already unlocked when you get the game. then five is unlocked by completing the campaign on any difficulty. then dead ops arcade is unlocked by escaping from the torture chair in the main menu and to do so tap RT and LT Repeatedly and entering a code on the computer behind the chair the code is DOA .the next map is ascension you download a dlc called first strike. then you get call of the dead by downloading a dlc called escalation then theres a map called shangri la which you get by downloading the dlc called anihalation.last you get the map moon and the 4 remake maps from world at war by downloading the dlc called rezzurection.I Hope This Helps

if you get map packs on each map their are different and sometimes more objects to be used in forge.