The Draka attacked Greece through land, air and sea. Crete and the Dodecanese were defended by the Hellenic Navy and the Regia Aeronautica. The Hellenic Navy had undergone modernization, getting one Bismarck-class battleship and four Greyhound-class destroyers.
The Drakan Navy won the battles of Crete and Dodecanese, sinking the Greek and Italian squadrons, but it was a pyrrhic victory, since the Draka had themselves lost eight destroyers, five battleships, nine heavy cruisers and five light cruisers (in Crete), and one aircraft carrier (the DSS Adelbert), four battleships and eight light cruisers in the Dodecanese. The Adelbert was lost to kamikaze attacks (from damaged fighters).
The Draka started to invade Crete, the Dodecanese, the Cyclades and Sporades through airborne landings, but faced heavy fortifications, well-equipied Greek and Italian units, and a population willing to fight to the death. Many inhabitants were Turk refugees who had fled in 1918, or their children.
At the same time, the Draka were invading Western Thrace, from Edirne and Kesan. They won pyrrhic victories at Komotini and Xanthi, but took Alexandropolous easily (with naval support). Then, they took the island of Tasos, close to the mainland, allowing them to take Kavala, and won the Battle of Crénidès, thanks to a pincer movement (with forces coming from Kavala and from Xanthi). Finally, they managed to take Drama (in a pyrrhic victory).
The Draka were forced to pause and wait for reinforcements, before their thrust to Thessaloniki...