Beachhead (Halo Wars level)/Walkthrough
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The first several objectives are very easy. For rescuing Anders, lead her to the Pelican that is destroyed and then down through the teleporter to the beacon. Once you reach the beacon, all you have to do is hold off the attacking Covenant forces for 90 seconds and Anders will be rescued by another Pelican while Red Team arrives via HEVs to assist. Afterwards, simply follow the arrow and make your way from location to location until you have to capture and hold 4 bases.
Move your troops over to the southern Covenant Base and capture it. Quickly have your units take over the Locust and Wraith vehicles, after which you shouldn't have any problems with taking over this base. Build your own base at the newly acquired base site and start out with two Heavy Supply Pads, two reactors (one of which you should upgrade), and four turrets with the Missile upgrade to protect you from constant aerial Banshee assaults.
You can also collect the resources nearby the base, after which you should focus on getting the entire fortress off the ground. Be sure to have a Barracks, and upgrade the following things: New Blood, RPG, Medic, and ODST Super Units. It's now possible to spawn ODST troops anywhere you already have troops, by selecting it from the menu by pressing Up on the D-pad (Spirit of Fire Menu).
Move over to the other bases and start taking them over. There is an abandoned Scarab south of the second base you take over, so clear it from the Flood tentacles and have one of your Hero hop on to cause devastating damage to any upcoming bases.
The last two bases are to the east and upper regions of the map, and the last requires to travel through a transporter. As for the Skull on this map, return to the Flood base nearby the transporter you used at the very beginning of this mission and you'll find it. The 13th Back Box can be found on a high cliff on the right side of the second (lower) transporter that you used, and you will need a flight capable unit to get to it.
There's an another method to capture the Covenant bases. First, capture the nearest base to you. Build 2 reactors and upgrade 1. Then, build an air pad. It is up to you to build 1 or 2 air pads. Train as many Hornets as you can. Fly the Hornets around the map. Find the remaining bases, and capture them. The guards guarding the bases are only Elite Guard. They cannot attack Hornets because they are wielding Energy Swords. However, using this method may cause you a lot of time on Heroic and Legendary.