Aya: Blade of the Goddess (Main Quest)
This one becomes available immediately after finishing Way of the Gabiniani. As Aya warns you, once you start this one, you'll be committed to it for some time to come.
Next stop- the coast.
You're back on the boat, which of course means more sea fights. The tactics are the same as before- pick a target ship, and keep that ship between you and other enemies while you hammer its weakpoints, and shield/counterattack from its volleys, firebombing at close range.
First you'll face a wave of two enemy triremes, then a wave of three. Sail on after that for a cutscene in which things get worse.
Now you'll be facing two triremes and an octoreme, while surrounded by fire.
The flames form an not-quite-complete circle around you- navigate out of this circle as soon as possible. Otherwise, tactics are largely the same, but remember to use your new catapult ability, and recall that the octoreme always fires multiple volleys in quick succession.
Winning this round ends the naval combat portion of the mission (and, as before, your ship is so tough it's pretty hard to lose). Enter a cutscene that ends with you and Apollodorus smuggling Cleopatra in to see Caesar. All you have to do here is follow the leader- nothing else happens.
When you reach Caesar, another series of cutscenes play.
When you regain control, you, as Aya, have to find a way into Alexander's tomb. Go down the step on the east side of the room, somewhat hidden by the crimson curtaining.
The blocked door is an investigation area, but the plot advancer here is smashing open the weak section on the lefthand wall.
Follow the passage down to an apparent dead end. Smash the three pots to reveal a way through.
Dive into the sewers. Such glory.
Swim west through a missing grate into a much larger area.
There are many things to loot here, if you're in the mood, and there are air pockets up top for you to catch your breath. When ready to move on, aim west again for another ungrated tunnel.
Surface, and follow this series of annexes to a crack in the wall.
Press through into Alexander's tomb.
Loot the detritus and examine the artwork. When you're done, open the door to the monarchs.
When the cutscene ends, Aya will be tasked with a rescue mission. If you don't know the best way there, just follow Bayek.
A good point of entry is by climbing up the outer wall and making for the south battlement. This will give you easy access to the roof of the target building.
Slip in through balcony.
There are two guards inside- a heavy and a spearman. Kill them both.
Talk to the wounded man for some key intel. Then you're going to have to carry him out of here.
Start by taking him downstairs, then set him down for a moment- long enough to slip outside and off the guard at the target range (just to your left and you exit the east door).
Go back for the emissary, and take him out the door and south, to where a horse is waiting just a stone's throw away.
Mount up and go dead east, then turn north to get out of the fort. You are skirting close to the edge of the mission area, but this is the quickest way out. Ignore any guards enroute.
Return to the palace via dead reckoning. It'll mean bashing about a number of small staircases and alleys, but nothing here will really slow you down.
Reaching the palace triggers more cutscenes, ending with Aya about to assault the Pharos lighthouse.
Race up the scraggly branch here to the yardarm of the nearest ship. For the next crossover, be sure to drop down to the other spar, rather than jumping. Jumping can have unpredictable results.
Partway across you'll be automatically dunked anyway. This sequence gives no points for creativity, so just swim straight to the marker (hope that dust was waterproofed).
Once ashore, kill the first two guards you encounter. The ones inside will be too busy fighting other soldiers to pay attention to you.
Ascend the lighthouse as before, by climbing up the southmost seated-figure statue on the western side of the lighthouse, and leaping over the corner via the pulley there (see more detailed instructions in our location guide to the lighthouse here).
Once you swing inside the window, there'll be three guards to fight in the dirt ramp area. Use Overpower both to knock aside shields, and also to quickly leap within killing range.
Reach the top of the ramp and, as before, go out the open window, and climb up to the next open window.
Here you'll face the Guardian, a heavy bruiser with a giant maul.
The entire room is set up for you to use fire against him (eg the straw, the oil jugs, the arrow stands and lit braziers), but frankly it's easier to just take him apart with your blades- dodge his clumsy charges, then leap in with an Overpower stab while he's struggling to pick up his hammer again. Use your adrenaline attack whenever possible to stack up the damage.
Kill him and unbar the door up.
Climb up to the flame and interact with it to spur a concerning cutscene, and end this chapter.