1: as a Roman faction you only need worry over the Egyptian chariots. The Seleucids get wiped out by their neighbors almost 100% of the time, and the Britons are too far away from the center of the world (Italian and Peloponnese Peninsulas). Fighting Egypt comes first to the Scipii, second to the Brutii and latest to the Julii.
While Chariots break your formation remember that units sent flying are not auto-killed. I advise you to start off with the Brutii and follow the numerous strats and guides for them. They are the easiest to play early on. See the Brutii section in these very forums, I've written a couple of walls of text there detailing my start and transition into mid and late game.
Once you debark on Alexandrian shores the Egyptians will have already conquered Mesopotamia. However, with your high experience and upgraded troops you will hold your own versus their chariots. Getting 3-4 stacks of Gladiators helps immensly versus chariots as well as getting some Auxilia. Remember never fight Egypt before the Marian reforms. Even if you lose a stack so long as your 10 star general is alive you can replenish quickly in your main troop production centers (Italy and Greece).
2. Practice practice practice. Always plan out your deployment and assign troops to be flankers. The best flankers for inexperienced players are cavalry, because they are fast and have a high charge bonus.
3. Just right click on the wall. There are several sections that can be attacked, apart from the towers. But you can't attack wherever you like.
4. Early on, hold the line with hastati and run some Veities behind their backs. This will slaughter them. Fighting them when they are defending a city requires superior numbers.
Later on just use your pila and charge your better trained and upgraded cohorts at them. Urban cohorts smash trough phalanxes 1 on 1 in a fair fight. Don't be afraid, once you charge and run past the spears, they switch to swords and then they die pitifully to roman infantry.
Or master the good ol' hammer and anvil with cavalry (see point 2)
5. Rome has it easy. Build roads, then temples, then farms, then ports. Take your armies and start on a conquering spree. If you are Brutii the moment you take Athens, Corinth and Sparta your money will be more than you can spend. Remember roads + ports everywhere! Don't over recruit units, as their upkeep makes you lose money. Only recruit as many as you need to win. With your back protected by your Roman allies, you will usually fight one or two factions at most. The Brutii war machine is perfectly capable of stomping trough the Greek Citis AND Macedon at the same time. Just remember to always be attacking and building infrastructure.
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