Greece

The Kingdom of Greece is a small Balkan country located at the southern tip of Europe. Historically, Greece had joined the allies and was then invaded by the Axis, forcing them to capitulate. Greece plays similar to Yugoslavia but unlike Yugoslavia, has defensive chokepoints in its territory. Unfortunately, Greece can be attacked from two angles which can spread Greek defences dangerously thin. Due to its proximity to Europe it is recommended for newer Greek players to go axis as soon as possible before Axis declares war on you and force you to be Allies.

Strategies
Greece is small and does not possess much land or cities. Greece should first capture the neutral city directly north of their starting location. Build up your economy in the meantime. It is recommended for Greece to go for a pure infantry force with plenty of rocket infantry and supplemented with AT guns, a fairly cheap and easy to build army that can defeat most mid-game armies.

Join Allies
It is not recommended to join the Allies if you are a newer player. Prepare to defend yourself. Spam bunkers along your border. If Greece and Yugoslavia both go Allies they can form a strong Balkan front that can pose a direct threat to the Axis. Another avenue of attack is to land a few construction SCVs on Italy and build bunkers there, attacking the soft underbelly of the Axis forces.

Join Axis
It is possible for Greece to land on Africa and begin taking land there. Use a infantry force mainly comprised of machinegunners and medics and tech up to rocket infantry. When Operation Barabossa begins, Greece can be a huge help to axis forces, rocket infantry with the 'shaped charges' (700 science) upgrade will destroy Russian tanks with impunity when massed together. Greek forces should use their strong infantry force to protect the flanks of advancing Axis tanks, taking cities and giving the other Axis players the freedom to press forward and destroy key infrastructure, ridding Europe from the Soviet threat once and for all.