Antigonus II gonatas acheives a staedy rule in macedonia and a stable invasion of greece.
This will lead to macedonia getting careless and its loss of Greece, a major impact to its borders, ultimately becoming a roman province in the long-run.
This is an event that has to do with the fall of macedonia. Its borders slowly wittled away time due to alexander the greats death. This leads to more frequent invasion. in an attempt to re-enlarge thier border, they attack rome. the army is deafeated, the plan backfires and macedonia turns into a roman province.