The first Halo had a great story
LOL IT MAKES ME COOL TO NOT LIKE GOOD GAMES RIGHT IM SO REBELLIOUS LOLOLOL
Also I'm not trolling, does this look like The Sewers to you?
You start off on a ship you have just woken up and you are ass deep in a battle with fucking aliens fuck. You spend the first 5 minutes defenseless running through a ship as your friends get murdered like the jews they are. Then you get a pistol with no ammo, so now it's up to you to run through hell bashing your way through midget aliens hopelessly trying to find ammo. Then you actually lose the battle and you are forced to launch an escape pod onto a near by ring known as Halo. So now it's up to you to go find survivors and get your ass off. Sounds easy but the aliens were heading here in the first place so now they are there too. Oh so you spend a few days fighting them off and your best friend the captain gets kidnapped. You go save him and your friend somehow finds himself lost again. Well this time while looking for him you find yourself a bloody suit of marine armor. You playback his last memories to find out that he was ripped to shreds by zombies/parasites known as the flood. But these aren't your typical zombies/parasites. First they start out as cute little bugs that rip your friends to pieces and manifest themselves into their bodies and make your friends who are pretty decent fighters into fucking hulks of organic matter that will lunge themselves at you and rape you.
Oh right did I forget to mention they can still use guns apart from the usual zombie rapage. So now you find out that with the new addition of the flood, the covenant (aliens) are still out to rape you too. NOW its a 3 way war as you set out to destroy Halo and get rid of both the Flood and the Covenant. Well along the way you meet a cute little robot known as Guilty Spark. He is the remainder of a long lost race of aliens known as forerunners, who built Halo. Well Guilty Spark tells you that he can help you destroy Halo, and after calling Cortana (the A.I. in your suit of armor) a bitch, she doesn't trust him anymore. This is good though because what you don't know until towards the end is that if Halo gets destroyed then it sends out signals to all of the other Halo's to activate and destroy the universe by sending The Flood every fucking where. Oh but it's too late and you have already caused Halo to self destruct. So now you have to get your ass off the ring and right when you do the game ends. I'm not even going to go into the Covenant side because it is so deep it would take an hour to explain. They're basically set to destroy the universe using Halo as part of a religious cleansing, even if it means taking themselves out with it. And in Halo 2 you meet The Arbiter who is like LOL FUCK THAT and joins your side. Around Halo 3 all of the Elites join your side because the Brutes are fages and listen to whatever the Prophets tell them to do.