Mass Effect 3/Prologue

For the purpose of the guide, your character is a male/female Shepard, a soldier/sentinel, born in Earth and a sole survivor. The person you rescued is Ashley/Kaiden and you have no love interests with any characters in the series. However there will notes pertaining your actions or your gender towards a character you want to hang out with. Lastly, the dialogue choices will be skipped except for the important parts of the story.

Reapers come to Earth with a bang!
Shepard is greeted by Vega. Mr. Anderson brings you to the council area. Along the way you meet Ashley/Kaiden since he/she has been promoted. Anyway after trying to convince the council, the Reapers struck leading to a major bang with the council leaders decimated.

Shepard's first strike
This is a relatively basic tutorial to get the hang on the controls and how it works for this game. Follow the instructions as you and Anderson tries to get out of danger. For a few reapers climbing up walls, try to shoot them. Make sure your crosshair turns red for a much better accuracy. After you climb down the ladder. Shoot one reaper on the left. Then melee two more and one coming over the rails to greet you. A giant Reaper shoots a beam leading to exploding glass and fire. Anyway, when you reach the door, do a strong attack then press the action button to open the door. A cutscene have you trying to save the kid but he disappeared. Take note as the ending will have that kid in a different light. Anderson takes you across the building cliff to move you along.

Shoot your way to Normandy
Get the ammo and reload. As you reach the docks, you came across a slightly more bigger reapers. Use cover and shoot your pistol at the enemies on the other side. Then go across and right and finish the rest off. You'll reach a few soldier with one with the leg stuck at a building structure. Take cover and shoot again at the reapers since you can't get across. When it's clear, talk to them and they free his leg. Continue to now a bridge to get to the radio.

Normandy to the rescue
Continue taking out the reapers as you get to the section with three boats in a line. Pick up a machine gun for a final shoot down. Take cover and take out as many reapers as you can before the Normandy blows the reapers sky high. The cutscene kicks in which Vega and Ashley/Kaiden catches you. Anderson decides to stay and gives you his badge to reinstate you as Commander again. As a sad note, the kid that got into a high tech police is shot down which will play into Shepard's dream sequences far later on.