Alpha Base (level)/Walkthrough

Walkthrough
This level is more like a "training level" to help you understand the basics of the game and introduce you to campaign mode. In this level, you are playing in the role of Sergeant John Forge and his Gauss Warthog, attempting to reassemble the marines who were originally stationed at the run-down Alpha Base but were run off by Covenant forces.

First off, drive the warthog to the arrow and keep driving in the direction of the arrow. Eventually, you will be lead to a few enemies, so press the X button and slowly take them down. After you kill them all, keep driving in the direction of the arrow.

After you reach your first squad of marines, they are pinned down next a three squads of Covenant. You can't control them now, so drive Forge into a safe direction and kill them one by one, with the support of your marines. After they all die, they will get in a Warthog, giving you two warthogs to toy with.

Keep driving in the direction of the blue arrow. Every now and then there will be a few bumps in the road (Covenant) so kill them by making Forge kill one squad and the other marines to kill the second. After a few Covenant encounters, you should reach another squad of pinned down marines.

There are much more Covenant in front of you this time, so take the same strategy again by making one squad kill one squad, and another squad kill another. Once you defeat them all, your marines will become usable, but this time they are foot soldiers, and will not have a warthog.

Go into the same process, follow the blue arrow to the base, killing a few Covenant on the way.

After a while, you will reach a barrier with a few squads of Covenant guarding it. Your warthogs will not be able to pass through it, but instead you will have to assign all of your foot soldiers to pass through it. Kill all of the covenant first, and then attack the power core with your marines' Y ability. Once the power core is broken, allow all of your units to pass through the barrier.

Keep following the blue arrow. Your next stop is the base its self, so be prepared. Let your Warthogs pass through first, and use your marines to kill the guards.

Once you enter the bases interior, there will be Wraiths in the middle of the base. Do not attack this, as there is a Shortsword bomber that will kill them for you. You will then have to kill a few squads of Covenant on all four corners of the base. Send your squads one at a time and kill them quickly with your Y ability. Once you kill all of the Covenant, your mission will end, with Alpha Base online and running once again.