Retaliation is set up as follows. Near the center of the mission, there are two towers that are very close to each other. One tower is for each team. The towers house the flag and an inventory station both protected by a team-only forcefield. Each team also has another structure that houses the flag forcefield generator. As you can probably guess, when the flag forcefield generator is destroyed the forcefield around the respective flag is brought down. In this manner, the enemy's (or your) flag forcefield can be brought down and the flag can be taken.
The flag generators have a system of force fields that work for them. These forcefields are only inside the flag generator's building. They work the opposite as the typical forcefields. Let's say you were the one destroying your enemy's flag generator. Once you destroyed it, multiple forcefields would come up trapping you inside the building. In this fashion, hit and run tactics become near impossible. There are ways around this but I believe the intention was to make it difficult to keep the generator down by camping it, etc.
Something that I noticed was that the forcefields around the inventories (in the towers near the center) never go down as far as I could tell. Hypothetically, someone could sit in there all day with the flag if they wanted to. However, this 'turtling' method would probably end up with the player being harassed/kicked/tk'ed.
The main bases you won't see a lot of. These bases are seperate from the towers and flag generator buildings. The main bases have vpads with access to havocs only. This is useful for massive assaults on the flag generator building. This is because the flag generator buildings are set up so that the enemy's is the closest building to your main base.
This map is a lot of fun with large amounts of people. You dread the message "your team's flag generator has been destroyed" and the "dun dun" that emphasises it. The map can be won very quickly even with the cap limit at 10. The motto for this map is "the more people the better" because it is not as fun to play with small numbers of people.