You've probably been wondering where Markos has been since the beginning of the game? Well he's relocated to the Highlands of Asklepiades in Kos, though he's found himself in a bit of a pickle with some locals regarding vineyards. The more things change, the more things stay the same. You'll need to help him out to complete his quest-line.
Markos side quests guide
If you want to explore a different region, head back to our Assassin's Creed Odyssey side quests guide for a full list of the different regions. Alternatively, there is also the Assassin's Creed Odyssey guide for everything else.
A Business Opportunity
You'll eventually find Markos chained up on the island of Kos, towards the middle of the island and not far from the Highlands of Asklepiades. There will be a small prison underneath some shelter. Unlock the cage and carry Markos to his vineyard up the hill. He will then tell you about his "mama", before asking you to take some wine to the Cerberus. He never exactly eludes as to whether he means the three headed dog or something else.
Head to the waypoint to find a house near the Kos Herb Fields. The soldier in the courtyard is the one you are looking for. He'll be sceptical of the "peace offering" and offer you to drink with him. If you do so, he will claim the wine is poisoned, so return to Markos to find out that it isn't really the case, just really bad. It turns out though that the soldier has two brothers, hence the Cerberus moniker.
Farm in Flames
You'll then be tasked with burning their farms, three points in fact. Each one has its own waypoint so head on over to find three silos. Take out your torch and hit it a few times, before running back. It will then explode, burning the nearby area. You will accrue a bounty as a result of your actions. Head back to Markos to find out that he sent you to the wrong farm... After pleading with you, he'll offer "mama"'s axe. Agree and kill the five level 28 goons that invade to get Markos's Wine and Markos's Gift (the axe) as a reward.
That's all the side quests for this questline. Head on back to our Assassin's Creed Odyssey side quests guide for more information about another quest-line or another region's set of side quests.