secure mainland Greece first, take it from whoever it belongs to ATM.
Do like Napoleon said; begin from the south and slowly work your way up north.
Once you've reached the Danub banks, turn west and expand through Illyria.
You should have encountered the Brutii by now (hostile waves of green troops)
Settle your defence around Salona; the city is close enough from the rest of your greek settlements so that reinforcements can get there quickly.
ATST, every time you repel an offensive, the Brutii will have a long way to march between Segestica and Salona.
It should buy you time to prepare a campaign in southern Italy or Sicily.
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