Halo Atonement is the upcoming sequel to the famous FPS, Halo 3. It takes place 4 years after it in 2557 and The Covenant has returned under the rule of the Brutes and few remaining Prophets. The game centeres around ODST Drop Team 215 and it's leader Sgt "Bishop" Andrews.
The game opens in 2557, the humans are pinned down on the ground by an unseen force, one of the Marines attempts to escape but is tracked down and executed by a large Brute in black Chieftain dress with a customized Energy Sword. As the game progresses the basic summary of the backstory between Halo 3 and this game is narrated by Corporal "Knight" Peterson, Bishop's second in command. He tells of the war between Doisac, the Brute's homeworld, and Sangheilios, the Elite's, and how the Elites failed to claim their Covenant back, resulting in de-facto control of the Covenant by the Brutes and Prophets. With their strength a new, and at it's apex, higher than it's ever been before, mankind holds it's breath for what might be the greatest war it's ever seen. He explains how he is sure humankind is going to loose this war.
The first mission opens on the UNSC "Aegis Fate" a frigate on which 215 is stationed. Bishop is seen leaning over a hologram of the planet as he remembers 215's briefing by General Moran. As this is done, Knight arrives to give Bishop a helping hand getting the drop pods loaded and ready for deployment. As he does this, they are greeted by the other two members of the squad, Lance Corporal "Rebel" Stephens, and Lance Corporal "Dixie" McNair, who inform the Sergeant they have two new recruits, Pvt "Wolf" Brown and Pvt "Anytime" Green, both of which are extremely skilled in heavy weapons, though incapable of 'replacing' Knight, the team's current all time heavy weapons demolitionist. As they greet they get a call from Moran that it is time. They proceed to enter the drop pods, inbound for Pelican Refuelling Platform B-5, in an attempt to find out what they were trying to do there, and possibly find some clues as to what they are planning.
The next mission is actual gameplay, the player starts off the level with an M7S Submachine Gun and M6G Magnum, who's objective is to link up with Knight. Once doing so, after fighting a handful of Grunts and Jackal, finds out Private Green was killed in the drop, his feet telescoped and he was crushed as the pod went to deep, killing him under the pressure. Once there, the duo take out some Jackal Snipers and some more Grunts, and Knight offers to provide a distraction whilst Bishop goes in 'the back door'. Bishop goes inside and confronts a Brute pack lead by a Brute Captain. Bishop succesfully eliminates the threat and finds a video feed. He plays it back to find out the site was visited by a Brute Chieftain of some sort, accompanied by several Brutes with strange glowing devices on their backs. Upon doing so, he is ambushed by yet another Brute Captain, after a short brawl, the Brute overpowers Bishop, and as it is about to execute him, the Captain is finished off by Rebel perched in a sniping position. After the five regroup and begin discussing their next plan, Wolf is executed by an unseen Brute, who then incloaks revealing himself to be the Brute Chieftain that had attacked the base, however, before the team can react, the Brute escapes.
In the opening suite of the next mission, Knight and Bishop discuss the recent deaths of their 2 newest recruits in the side seat of a Pelican dropship. Bishop says he recognizes the Brute's limp, as an adversary called the 'Spec Ops Commander' he fought back during the assault on Voi, claiming the Brute killed his entire platoon. Their next mission is to find and secure the location of Marine Platoon 195, who recently fell under unnaturally heavy fire from a Brute pack. Moran states the Platoon has been reduced to six men, and that they were attacked by a strange Brute Chieftain in dark armor. Bishop and Knight exchange glanses to this. It is then Knight asks Rebel to cover their infiltration of the enemy territory upon dropping. Rebel says he's got it, and the mission begins with the player controlling Rebel. Most of the level requires stealth and evasive meneuvers, even though there are very few powerful enemies, most of the enemies faced during this level are low ranking Brutes, Grunts, and Jackals, mainly Snipers, however the Player must fight two Hunters at the end of the level. The mission starts in the side seat of a Warthog (the player can choose to drive). Rebel traveled with the warthog convoy, Knight and Bishop in front, Dixie in back, you're in the middle. Rebel then gets out and takes an elevated side path to cover the convoy. The entire first half of the mission is this, then the last half is defending an outpost from waves of Covenant Grunts, Brutes, Jackals, and several Hunters (Drones on higher difficulties)show up and the player must eliminate them and escape from the area before Brute Chieftains are sent in. Luckily Rebel does not have to fight said Chieftains. The level ends with the team meeting up with a crazed Marine from the 195 saying the rest of his team fell out of contact when they saught refuge at an abandoned city, and how they never came back and all he heard was screams. He then speaks of demons from hell, and then shoots himself.
The fourth mission takes place during night. The four lone ODST's shine their lights across the abandoned city searching for the missing platoon. The player is back to Bishop in this one, starting with his weapons. As the level progresses it gets darker, and fog begins to thicken. Shapes can be seen in the fog and deformed bodies, soon, Admiral Harper tells them an LZ is set up on the other side of the city, and alerts the team that there may be something other than Covenant in the area. Finally they come to an abandoned warehouse where they are attacked by none other than Flood. Rebel suggests the good Admiral is hiding something. As they progress deeper into the city and fight Flood infected Humans, Brutes, and Helljumpers, they finally stumble upon the remains of 195, a mere five Marines, one Helljumper. Bishop and the helljumper, who reveals himself to be a Sergeant Miller, confront over rank, Bishop reveals himself to be higher to being Sgt longer than Miller, and Miller turns over the title of CO to Bishop, who then suggests they team up. Miller rejects, saying that he'll gladly give him two of his soldiers, a Marine Sniper, Lance Corporal Kramer, and a PFC Marine Pilot Anderson. Afterwards, him and the 2 remaining Marines depart and keep 215 posted throughout the entire mission.
The mission ends when daybreak begins. The team finds themselves and their new members staring death in the face when loads of Phantoms, including one with a Brute Chieftain lands in the courtyard separating them from their freedom. This mission you play as Knight, and must arm explosives set by Anderson to demolish a bridge to prevent a Covenant invasion party passage, however, a Brute pack gets across accompanied by the Chieftain. The Chieftain manages to kill Kramer who was covering Anderson and Knight, and he then goes after Knight, who kills the Brute Chieftain preventing him from harming Anderson. Knight feels guilt for Kramer's death, but Rebel tells him to toughen up, people die all the time, of course, Rebel succeeds in making Knight feel even more guilty.
The opening of the next mission includes the opening cutscene an enraged Knight strikes Admiral Harper across the face, and demands he tell him what Flood are doing on Earth. The Admiral succumbs after more punches from Rebel and kicks from Dixie, and he tells them that they, the ONI have been doing experiments lead by Captain Sortor, and now they've broken free. Bishop tells Harper he may have endanged planet Earth, and appologizes for his team members' behaviors. Harper says that the Brute Commander that arrived on the Assault Carrier 'Divine Ascension' is building a bomb which he will use the still functioning monorail at Arusha to transport it to UNSC's new headquarters under the ruins of Voi. It then becomes 215's suicide mission to detonate the bomb BEFORE it exits Arusha, which will surely insure the entire destruction of the surrounding area of infestation, but that they must leave for Arusha now. The mission officailly begins on a Pelican, which gets shot down in the middle of an African Svannah near the ruins of Tsavo Highway. The player, which is Bishop again, must lead the team through intense vehicular combat until they get to the higheway, which, instead of taking the Voi route, take the Arusha route. In this level several Brute Chieftains are fought, including a War Chieftain with a Gravity Hammer, and Drones (Hunters on legendary). The mission ends upon reaching the ruined entrance to Arusha.
The seventh and final mission is all Flood. The player is Rebel once again and it is your objective to cover the team's succesful boarding of the monorail, including through a ruined office building and across a flood infested bridge. Once there, the player must fight his way to the forward-most car, where Bishop and then Dixie are knocked comatose. Knight tells Rebel to cover him while he detonates the bomb. The Player's REAL objective is when the Commander himself shows up, to fire at him until he activates his invulnerability. You start out on top of one of the cars, but we recommend you jump down to get into the real action if you want a real challenge as he has dual energy swords and can kill you in one slash. If you or Knight dies, the mission is a flailure, but once you get him to activate his invulnerability, the mission ends with the final cutscene of the game. The commander runs at Knight who ducks out of the way once he realizes he cannot damage the beast. The commander roars and choke slams Knight with his free hand, raising his blade above his head about to execute Knight, however, Rebel saves Knight's life by ramming Bishop's combat knife into the creature's jaw, the Commander then topples over the edge and supposedly dies. As Knight and Rebel wait for death, a Pelican shows up, piloted by Anderson, who extracts ODST Drop team 215 at the last minute before the bomb goes off, destroying Arusha and all surrounding infected cities.
the final cutscene is a cliffhangar, 195 can be heard in the background taking heavy fire, and 215 is seen climbing atop a large mountain, overlooking most of eastern africa, only to see, to their dismay, a massive fleet entirely comprised of Assault Carriers enter and begin glassing Earth.