The first thing you should do is collect the bottle on the left.
Note the fountain on the right this might be useful later on.
Use the bottle or your bare hands to finish the guy patrolling around.
Pick up the weapon he looses.
Continue through the gate at the end and finish the next guy.
Find the second pedestal with fern and climb onto it.
Take a running jump towards the higher platform opposite.
Climb onto the roof.
Run along to the left and take on the next baddy.
Run up the stairs and through the archway.
Follow the tunnel to a balcony and finish the guy there.
Collect his weapon.
Notice the chain on the left.
Jump onto it.
Climb down and drop onto the walkway.
Cross the bridge.
Climb onto the lorry and break the box to get a medikit.
Then continue to the other side and finish the guy.
Collect his weapon.
Then run along the right side of the castle wall to find some ammo in the corner.
Now run to the other side of the bridge again.
Run down and turn left.
You have to take a running jump to reach the pipe.
Shimmy right on the pipe. Drop down and use the whip to reach either the next rope or the safe ground.
Walk along to the left to get some ammo and another weapon.
Then go to the right end.
Climb up and open the door.

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