Are You Not Entertained? (Side Quest)
This quest actually has two quest markers, both in Kyrenaika.
Speak to the Lanissa at the southern marker to hear about a bounty on a crazed escapee gladiator.
Follow him across the yard, then fight three of his men to prove your worth.
Your worth proven, you'll get a clue about Silphion Farm to the east.
You can locate the local treasure at the north end of an L-shaped building.
Open the red chest there to complete the location.
You're also likely to notice the lions.
They tend to attack one by one, so melee weapons are fine for them. There are several clues scattered around the farm, but the plot advancer is the wooden trap door in the elbow of that L-shaped building. Open it up.
Downstairs you'll find a note from the gladiator, and a clue to his current whereabouts.
Use Senu to find him on the coast.
Talk to him. He's not happy to see you, but he will tell you where he threw the Lanissa's sword. Senu can pinpoint that too.
Dive down and snag it from the ocean floor.
Catch up with Polymestor to find a confrontation afoot.
When the talking ends, kill all the Romans, including the Lanissa.
Nothing too tricky about these no-names, particularly with the gladiator backing you up. When the killing's done, talk with him one last time to complete the mission.
You'll also get to keep the sword, but it's only a rare.