I'll just copy and paste the readme:
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Halo 2 Mod Version 5.31
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Mod By: NiTrOuSoXiDe
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Installation:
1- BACK UP YOUR EXISTING MAP FILES!!!!!!!!!!!!!
2- Apply bloodgulch.ppf to your bloodgulch.map file
3- Apply sounds.ppf to your sounds.map file
4- Apply bitmaps.ppf to your bitmaps.map file
5- Run the game and create a LAN game (to prevent anyone from joining your game, unless, of course, they have the mod as well) with all vehicles (to get a real sence of what the mod offers).
6- Join a specified Halo 2 mod server (look for IP's in the forums)
What's included in this mod:
1- Battle Rifle (Assault Rifle w/ NEW MODEL, modified skin, recticle, fire sound, weapon-ready sound, barrel flash bitmap, accurate scope sight and weapon specifications)
2- Guass Warthog (Warthog w/ modified skin, lights, recticle, fire sound, and weapon specifications)
3- Civilian Issue Sports Hog (Warthog w/ modified skin, lights and sporty enhancements including edited model)
4- High-Impact anti-aircraft tracking plasma launchers
5- Ghost has higher rate-of-fire yet causes less damage per landed hit
6- You will conceive damage upon crashing a vehicle into a wall or other object, including another cyborg
7- Brute's Grenade Cannon (Fuel Rod Gun w/ new model, skin, fire sound, detonation sound, projectile and more!
8- Sub Machine Gun (Pistol, w/ NEW MODEL, modified skin, recticle, fire sound, weapon-ready sound, reload sound and weapon specifications)
9- Covenant Sniper Rifle (Sniper Rifle with w/ NEW MODEL, modified skin, weapon-ready sound, fire sound, reload sound, modified projectile and weapon specifications)
10- HEX edited HUD messages (ex: Picked up a battle rifle)
11- Added and modified various sounds and sound effects and visual effects
12- Gravity Rifle (Flamerthrower w/ modified skin, weapon specifications and detonation bitmaps)
13- Dialoge upon entering/exiting Warthogs
14- Updated sound effects and visual lighting effects!!!!!!!!!
15- Cool new meshed flag look with chrome flag pole
16- New frag grenade model, skin and explode sounds
Fixes:
1- Pixelated explosions fixed
2- Rediculously overpowered turret addressed
3- FPS drop issues fixed
4- Netcode leading distances slightly decreased
5- Pixelated/discolored lights fixed
6- Out-of-sorts weapon skins fixed
7- Over-powered covenant sniper fixed
8- SMG sounds, projectile spread and damage addressed
9- Covenant sniper sounds added
10- SMG Hud message icon fixed
11- Weapon clones fixed
12- Red flag with blue color fixed
13- Over-forced Gravty Rifle addressed
14- Gravity Rifle hud message fixed
15- Battle Rifle scope fixed
16- SMG model more accurate to E3 video
17- Battle Rifle model more accurate to E3 video
18- Battle Rifle alternate sounds added
19- New, alternate and more forceful explosion sounds added
20- Rockets in SMG hud display fixed
21- SMG recticles fixed
Things to be aware of:
1- All custom models are TEMPORARY until the HEK is released!
2- DO NOT attempt to play with any of the modded map files on a non modded map, you will get severely undesired results. This is why you MUST BACK UP YOUR MAPS!!!!
3- Once the editing kit arrives, you will see extreme progress with this mod, especially the new vehicles and weapon models. Also, look forward to playing this mod with Mrs. DoubleFire's New Mombasa map!!
4- I need your opinion on the Warthog tail lights! Are they too bright? Do they look dumb?
Things to expect in further releases-
1- More accurately modelled Battle Rifle, SMG, covie sniper and other weapons
2- Halo 2 maps
3- Drivable ATV
4- Drivable Shadow
5- Drivable Wraith
6- Reskinned/ remodeled Blood Gulch with new ambient sound
7- More!
Special thanks to Molkien for the assistance he has given us!!!
Special Thanks to Doom Monkey for hosting the mod files and helping out with intense testing!!
Special Thanks to BBow for hosting the mod files and helping out with intense testing!!
Special Thanks to r0o0b0 for hosting the mod on his dedicated server!!
Special thanks to Halo_Sniper for hosting the mod on his dedicated server!!
Special thanks to all who have helped me in the ongoing process of creating/maintaining this great mod!!
Special thanks to Mrs. DoubleFire for the newer, better looking Guass Gun recticle, and for modelling not only the insane New Mombassa Multiplayer map, but some other surprizes too. You'll see when the HEK arrives

Special thanks to Dr. Lime for contributing some new models for the new guns and the information for the Brute Grenade Cannon!
Special thanks to STB for extensive testing!!
Special thanks to VALVe for some awesome explosion sound effects!*
Special thanks to GowmanAG and SpitFire for hosting this mod on their dedicated server!
Special Thanks to HellSpawnHere and his POS explorer for extensive testing! *still wearing flame suit*
Thanks to MonoxideC for making HMT, the main tool used in the creation in this mod!
Thanks to Grendiac for creating SparkEdit, a very crucial tool used in the making of this mod!
Thanks to everyone on the Gearbox and Halo Mods Forums who has supported me along the way while this mod pulled together. I couldn't have done it without your support! I owe it all to you guys!!!!!
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