To finish Halo, you have to successful go through all the hurdles and levels. The user manual has all the tricks on how one can go through all the hurdles.
Finish the Halo 2 single player campaign.
shoot aliens
Finish the Fight
well dude you clearly havn't finished halo 3 or you have finished halo 3 but wasnt patiant inouf to wait for the credits to finish wait for the credits to finish and then woopdie do mc [master chief] aint dead
Finish campaign on Normal
The main thing in halo 2 is when master chief is on a coventent ship that is headed to earth and he must finish the fight!
If you are already jumping to halo 4, stop and go back to halo 3, finish it to the end of the campaign and you will discover that master chief actually does "Finish the fight!" in this one, breaking the chain of halos and making the game, Halo, a trilogy. There are other games involving the concept of halo though like the most popular ODST, halo wars (a real time strategy not an FPS), and many more. If you aren't ready to stop there go to online multiplayer, in halo 3 with the new forge ability you can have endless fun with friends on modded maps made to meet your likings.
You don't even need to finish marathon man to get the security shoulders. All you need is 750G in Halo 3.
Play firefight match making be the last on alive in a wave and finish that wave.
You have to unlock it through achievements. Buck- Finish Tayari plaza on Normal Dutch- Finish Uplift Reserve on Normal Mickey- Finish Kizingo Boulevard on Normal Romeo- Finish NMPD HQ on Normal Dare- Finish entire Campaign on Legendary
there are alot of special achievements. one group are the new achievementsts put on by bungie, but there are also Vidmaster achievments, which are 1. find all the mythic skulls 2. in halo ODST, finish a level on legendary without throwing a grenade or shooting 3. in halo ODST, finish the last level on xbox live on legendary, with the iron skull on, only on mongeese 4. in halo 3, get to the rank of lieutenent on xbox live 5. in halo 3, get seven exp in any playlist on the seventh of the month 6. in halo 3, finish the last level of halo 3 on legendary with iron skull on, and only use ghosts, with 4 people over xbox live 7. in halo ODST, complete the 4th set on firefight on heroric, on xbox live with more people A great website to get help with these is achievementhunter.com, run by roosterteeth. Their videos will show you how to find tricks, and complete the achievements.
yes cuz a lot of people think he died from halo 3 at the end but he didnt cuz if u finish halo 3 on legendary theres an extra part in the last video on halo 3 that shows master chief not dying http://www.youtube.com/watch?v=IAFNynOMQZw halo 4 ign rewind trailer