How do I kill the merchant in the "Port Authority" mission without being detected?

One of Ezio's assassinations requires me to kill a merchant hiding on a boat without being detected by any of his guards.

He's being guarded by an archer on the dock (no problem), two patrolling guards on the back of the boat (no problem), two stationary guards near the wheel (kind of a problem), and two heavy guards right in front of him (huge problem).

What strategy, tool, or combination do I need to use to off this guy?

Solution 1:

Here's how I eventually succeeded at it.

1. Jump down from the roof, kill the guy on the dock from the water.
2. Climb up onto the rear of the ship, kill the patrolling guard when he comes by.
3. Same thing, different guard.
4. Hop off the ship, climb down, pull this guard, climb back up.
5. Wait for guard 7 to be walking away, then kill this guard...

6. ...and this one at the same time, with the double assassinate skill.

7. Here's the tricky part. Jump back over the side of the boat and wait until this guard is walking away. Pickup the body of guard 5 and toss him overboard. Go back over the side. Wait. Do it again for guard 6. This time, allow guard 7 to spot you before you go over the side. He'll go into suspicious (yellow) mode and walk over to investigate the spot where you were. There won't be any bodies so he won't go into alert, and you can haul him over the side.

8. Now that you have free run of the rear of the ship, hop up onto the rail and air assassinate.

Solution 2:

Taken from this post:

1) Dive into the water, either from the rooftop directly (move along the roof to the right of the mission start-point) or work your way down to ground level

2) Swim to the other side of the boat- DO NOT get too close to the boat until you are round the other side

3) Climb up the hull to the right-hand side section of rigging just until you are able to grab the top railing

4) Shimmy across until you are towards the back of the boat, just behind the 2 guards that are over-looking your target

5) Wait until all patrolling guards are away from you (you can try and ledge assassinate some, one of my friends said this worked however it did not work for me)

6) Climb up and immediately drop onto the deck

7) IMMEDIATELY drop a smoke bomb- you should have time to do this just before you are spotted

8) Run past all guards, jump onto the rail above your target, and air assassinate him... DONE!

Alternatively, as user bobbyrk puts it:

The way I did it, was first to swim around the front side of the boat, away from the dock. Climb up the side of the boat, and when the first guard gets to the back left corner of the boat, pull him over the edge.

You don't have enough time to slide over and pull the second rear guard overboard, so don't bother trying. The guard on the dock will return, you have to be about three meters from the rear of the boat for him to not see you when he reaches his stopping point at the end of the dock. When he turns and walks away, monkey over to the back of the boat, take out the second rear guard, then jump to the dock, and use the gun to take out the dock guard. That'll draw the attention of the brutes and the guards at the front of the boat if you time it right.

Get back in the water, and climb over to the left front side of the boat, near the forward stopping point of the patrolling guard on that side. When he gets there, pull him overboard. Repeat that process for the other patrolling guard. Don't bother with the two guards in the front end of the boat.

Circle to the back end of the boat, climb up and walk slowly up behind the two guards in front of the wheel. Walk between them so you stab both at once, and you'll be free to take the target out.

Solution 3:

Everyone made this mission harder than it had to be...

Climb the back left wall of the ship. Off the ledge, drop a smoke bomb. Move into position behind the 2 guards in front of the ledge above the target and drop a 2nd smoke bomb. Climb the ledge, then jump down for the assassination.

Piece of cake.

Solution 4:

ALTERNATIVE: GUN!! I found it very difficult to assassinate them all with a blade. Instead, I tried a gun assault.

First step: swim around the boat and wait for the one on the dock to get to the end of the pier, when for a moment he is facing away and looking out at the water. At the right moment quickly climb onto the pier and assassinate him from behind with the hidden blade.

Second step: sneak back up the stairs and assassinate the two guarding the stairs down to the boat from behind.

Third step: go to the bottom of the stairs and get just close enough to lock on to a guard, and assassinate him with the gun.

Fourth step: they will get suspicious and one will probably come up the stairs looking for you. Just run back into the city streets and stay out of his line of site until he turns back towards the boat. When he turns to head back to the boat assassinate him from behind.

Fifth step: continue locking onto a guard from the dock and shooting him, then run away and kill the suspicious one again as in step four.

Continue step five until you hit the target (when I did it he became suspicious and came to the side of the boat so I just shot him :D) or until you take out all the guards. MUCH easier! You're welcome :P