The Heart of Venice.
Level by Die Basis .
Open the Gate.
Throw the hidden lever behind the plant W to lower a block to a Secret later. Open the door E with the button and step out. Swim NW just below the surface and get out in the shallow corner. On the jetty N and pull the chain to open the door to the right, shoot the dogs there and go up into both windowsills S to get a Medipack and Flares. From the window with the Flares a jump up to the block N, then to the awning and traverse right to the lever NE, it will deactivate spikes on the wall S. Get down to that windowsill again and jump to the yellow bloc, turn around and jump up to the wall. Go use the lever E and the gate to the W of the canal opens up.
The Yellow Key.
Go out and get to the square W, up the ladder NW, to the level of the balcony. Hang against the wall and backflip onto the awning. Slide and jump hard right to land on a balcony (if you happen to slide backwards from the awning, grab the edge and shimmy left) Get the small medipack and jump over to the balcony E, grabbing it at the last moment. Get the Yellow Key there. Safety drop down and go to the canal. Swim to the SW corner and get up the shallow part.
Stop the Blade.
In the alley S is a ladder protected by a Blade. Open the gate NW with the yellow key, climb the balcony N for a Medipack and throw the lever on the block SW to stop the Blade, go check if it is in an open position, otherwise use the lever again. Go up the ladders, first one to the balcony then the other to the upper balcony and face S, hop back once from the S end, stand to the right against the balustrade and standjump with a sharp left curve into an opening in the wall below (Ctrl at the last moment). Shoot the glass, jump up and slide backwards down the passage left, grab the end and go over the jump lever to use it, big door opens E. Swim through those doors to the main canal.
Main Canal, Raise a Platform.
Go to that small island in the middle and on the S side is an underwater lever, use it and a platform goes up S.
Into the House, the Blue Key.
Swim into the S canal, climb up on the jetty with the big doors to the left. Face NE, jump into the windowsill and shoot the window to get inside. Turn right to the hall and push the button there to open the front door. Go into the room S and shoot the Owner of the house. Pick up the Blue Key he drops (when he dies on the stairs, you’ll have to look for it by hitting Ctrl on the stairs, because you might not see it) and collect a Medipack. Push the button SW to open a door upstairs.
The Waterskin and using it.
Go up the stairs E, push the button halfway up and get the Waterskin there. Go upstairs to where you opened the door and jump left (S) onto the awning, grab the edge as you slide off, go right a bit and pull up to backflip/roll/grab the platform you raised before. Jump over to the flat part of the awning W and climb into the building. Follow and shoot a Gangster, then throw a lever to raise a platform in the canal. Get out, into the canal and swim back W to the start of the level. Get onto one of the shallow corners SW or NW and fill the Waterskin. Swim back to the main canal and go left at that little island, up on the platform W and pour the water in the bowl in the yard. A Block and a platform go up at that white house looking left (S).
Use the Blue Key, the Crowbar.
Swim over there and climb up to a balcony with a curtain you can open with the Blue Key. Use the button S and enter the newly opened room. Around the corner left is a small medipack. Push the harp to the other tile S and climb the block, over the chandeliers to the jump lever above the entrance to open the other doors in the hall. Look in the mirror wall S to spot the Crowbar and take it with you to those crowbar doors at the canal. Just hop straight over the balustrade into the water and swim to the opposite side of the canal.
The Yellow Key,
Up the platform N and open the door, go up and through the ceiling hatch. Climb onto the chandelier and get the Yellow Key, open the doors E with that Key. Go into a small library, go to the slanted wooden panel in the back, stand back against it and take three steps forward, now backflip and jump to grab the monkey climb. Go E and left around the corner to a jump lever. It will open a door upstairs. Go back to the hall with the yellow keyhole and pass through the curtain W, go upstairs to the roof terrace. On a block with a zip-line is a lever, throw it to open a gate to the Torches. Climb the block.
Detour for a Secret.
Jump and grab S to the roof between the chimneys. Go over these small roof parts to the W and jump onto the roof W, grab the edge of it and safety drop down to the balcony below. Go onto the S end and jump over to the walkway S to getSecret #1, a Secret Rose.
N side of Town, a Torch.
Make your way back up through the crowbar doors to the roof and use the zip-line to get to a balcony, open the double doors to reveal a burning wall torch…
Go out and jump top the bridge N. Go left (W) and at the end is a Medipack to the right. There’s also the gate you opened, so get a Torch there and go back to the bridge, jump back to the balcony S and ignite the Torch. Back onto the bridge and head E this time. At the end left is the Fire bowl, no Wine yet, so leave the Torch there and get a small medipack from the balcony S.
Lower the block for the Earth Bowl.
Go to open the manhole in this street and climb down to use the valve, a door opens in the building next to the manhole. Go back up, shoot the right hand window S and hop in, through the curtain and opened door to a balcony in the S side of Town. Jump to the balcony E, here comes a tricky jump: you have to jump into the balcony NE. I stood back as far as possible and faced the opening between the first two pillars, Then I did the “short” run jump (hold shift, start to walk and release Shift, immediately hitting the Alt key). This way the balustrade will pose less of a problem. Now jump SE and grab the balcony on the E wall. Throw the lever there to lower a block at the crossing of canals below; it reveals another element bowl.
Dive into the canal and get back up to the bridge where you were with the Torch (Route through the crowbar door, swim W and on the right, through the red curtain and use the slide again). Jump N from the bridge into the canal and look E for an underwater lever under the bridge. It will open the door to the S side of Town.
The Holy Wine.
Swim to that tower structure on the crossing of canals and in the back of it, you find the block you lowered at the start of the level,Secret #2, another Secret Rose is yours.
Now go to the cemetery N and to the right (E) side and push the gravestone at the top of the steps aside to get the Holy Wine.
A Yellow Key for the Storage Room.
Dive into the canal and go into the one left (E) when you go straight under the jetty of the house in the middle of that canal, you’ll find an underwater lever, throw it and swim to the S side of the house. Up on the platform and now jump to grab up to the balcony S, get the Yellow Key there and swim to the end of this canal, get out and open the door to the storage room.
The Storage Room, a Carnival Mask.
Shoot the rats and crawl underneath the swinging crates. Pick up a Medipack behind the crates SE and go to the windowsill NW to get the Flares, now use a jump lever on the wooden pillar NE and a sprinkler will kill the flames. Go get the Carnival Mask and leave the storage room.
Use the Mask, up the chain.
Swim all the way W and climb out on the jetty left where you can place the Mask on the stand. A trapdoor opens at the chain W, allowing you to climb it, backflip onto the balcony.
Hop onto the table and jump to the balcony E, open the doors and get the Flares there. Open the doors behind it and go up the ladder to climb of left, go over the bridge and getSecret #3, another Secret Rose.
Raise the platform, open the gate at the Fire Bowl.
Go back to the balcony and jump back to the one W (don’t use Ctrl), now jump over to the N, then E and from the end you can shoot the window in the tower SE. Jump and grab into the tower. Crawl around to the other side and get down to use the lever there, a platform goes up at the house E. Shoot the window E and dive down to swim there. From the jetty you can climb the platform, jump to the balcony SW and go inside. Throw the lever to the right and the door opens, so does the gate at the Fire bowl as you can see when you step out, Put the Wine in the bowl and light it with the Torch you left nearby.
The Church, the Access Card.
Go into the church and get the Flares from the altar, then find a trapdoor NW, drop down to get the Access Card, climb back out from standing in the higher SE corner. Go SE behind the altar and use the Card there to lower a block. Get some Shotgun ammo there and climb the left hand ladder, backflip to the upper walkway.
Shoot the Church Bell, the Ashes of Paolo Lucio Anafesto.
Up W is a Bell and you can only shoot it from the block SW, go around to the other end and use the lever to raise the block. Go back to the block and line up to shoot the Bell, looking down you can now see a Bag on top of the cross on the altar. Go down and grab the Ashes of Paolo Lucio Anafesto.
Get out of the Church, dive down the S side of the bridge into the canal and swim up to that central little island where the block lowered you can now use the Ashes. A block lowers beneath you, on the W side of the island.
Flooded Underground Chambers.
Swim through to a flooded chamber, a Demigirl opens fire. Swim right around the corner and in the NW corner is the Shotgun, go S from there and on the pillar SW is an underwater lever, throw it to raise a platform on the S side of the room, swim E along the wall in the middle left is some Shotgun ammo. Then go to a Medipack in the SE corner. Turn around and swim up to the platform. Now you might have to lure the Demigirl in a position where you can shoot her as mine was under the platform at first. After she dies, she will leave a Key Bundle behind on the bottom.
The Heart of Venice.
Grab those and use them on the lock at the platform. The gate opens S, go in to get the Heart of Venice and pass through the next gate to end the level.