At the beginning of the Sandship, it's possible to skip killing the Electro Spume in the first sinksand. Run straight at the Spume until you almost reach its arms, then swerve around it. This saves a little time; a second at most.
It is possible to use Reverse BiTMagic to open the boss door in Sandship, thereby skipping the Squid Carving and enabling the Tentalus fight as soon as the Bow is obtained. The corresponding flag is 3x10. This RBM trick employs Faron BiT.
You will still need to obtain the Bow, activate the timeshift stone, and perform the mast skip in order to enter the boss room.
The corresponding flag in the Sky is talking to the Bartender after breaking the Chandelier. In this case, you should use BiTMagic to set 3x80 to remove the Lumpy Pumpkin Intro cutscene, and you can also use BiTMagic to set 1x80 to slightly shorten the Chandelier breaking cutscene and 0x01 to shorthen the Bartenders text. This method is faster when Faron BiT is set up with the Faron Pillar (allowing you to dive to the Lumpy Pumpkin immediately).
The corresponding flag in Faron is pushing the 2nd log in the woods, the one that is next to where you rescue Machi at the beginning of the game. Begin pushing the log off the cliff, then quickly start your file before the cutscene plays, showing the log pushed off the ledge. Then make an environment change (such as reaching and obtaining the Small Key), and the boss door will be open. This method is faster than the previous one when Faron BiT is set up with the Eldin Pillar method, however in this case it is faster to obtain the Boss Key by unlocking Skipper's Cabin with a RBM and BiTWarping in it.
At the beginning of each phase, sprint forward and do a running jumpslash to attack Scervo, then do a vertical spin attack. One of two things will be happening:
This can happen one of two ways: either the jumpslash and the spin attack landed, or Scervo blocked the jumpslash, started a slow attack, and the spin attack stunned him. Either way, stab until Scervo is knocked backward on one foot, then close distance with a jumpslash. Repeat this combo until he is knocked to the edge.
This happens if Scervo blocked the jumpslash and started a quick attack. If the spin attack does not stun him, he's about to attack, so shield bash his attack to stun him, then stab as above.
Following this strategy will defeat all three phases of Scervo. There are small differences between phases; in his second phase, Scervo will sometimes have a slight pause before a direct stab, making the shield bash timing harder. In the third phase, Scervo almost always blocks the first attack. But the same strategy works for all phases.
It is possible with a precise bow shot to hit the switch on the mast without going back to the main deck. In All Dungeons speedruns it is useful when combined with unlocking the Captain's Cabin Door and the BiTWarp into the Captain's Cabin, as it then skips having to go to the main deck completely.
There are two locked doors in Sandship, one leading to Scervo and the Bow, the other leading to the Squid Carving. Normally, one must go through the entire belowdecks section to get the second Small Key from the crew trapped in the brig in order to get the Squid Carving; however, it is possible to use Reverse BiTMagic instead to unlock the door leading into the cabin.
This RBM trick requires a file that has obtained bombs, but has not obtained the bow and not beaten the Imprisoned 1. The corresponding flag is Ex02, and it is set by entering the bazaar with that file selected, then speaking to the general item seller. Start your file and clear his second textbox simultaneously to perform the RBM, then commit the flag.
It is possible to skip climbing the masts after obtaining the bow in Sandship. There are three ways to accomplish this; the faster ones are generally the deathwarp or dungeon exit methods. The BiTWarp method is only used when combined with shooting the mast switch from the bow deck.
First, make sure you save at the bird statue in front of the bow. This is usually done before getting the Small Key anyway.
After obtaining the bow, exit to the main deck and shoot the targets on the lifeboat and the mast. Damage down to 2 hearts or less on the spiked grating covering the mast ladder, then shoot the timeshift stone to shift to the past; a cutscene will lock the door to belowdecks. Normally, dying at this point will reset you to a location just outside that door; however, it is possible to deathwarp while voiding out to respawn back at the bird statue.
Climb the left hand ladder leading to the upper part of the main deck, but do not move at all at the top. Pull a bomb, place it in front of you, then pick it up. Run straight forward until you pass the post supporting the lifeboat, then turn left and jump off the Sandship. The bomb should explode and kill you just before you land in the water; upon choosing to Continue, you will respawn at the bird statue. Use the bird statue to exit the dungeon, then reenter. Now when you shoot the timeshift stone, the mast cutscenes will not play and you can continue to piston segment.
After obtaining the bow, exit to the main deck and shoot the targets on the lifeboat and the mast. Position yourself close to the dungeon exit, then shoot the timeshift stone and, while the arrow is in the air, exit the dungeon via the ladder. Done correctly, the timeshift stone will activate and the cutscene will play partially before you leave the dungeon.
Reentering the dungeon will cause the rest of the cutscene to play, including the door locking. You can exit and reenter the dungeon one more time to unlock the door, then continue as normal.
This strat saves a couple seconds over the deathwarp method, but it is riskier. If you miss the shot or leave the dungeon early, you will lose significant time.
After obtaining the bow, shoot the target on the mast (and the lifeboat if necessary), but DO NOT strike the timeshift stone. This is usually done from the bow deck. Save at the statue inside, then activate BiT. Perform a BiTWarp with the Bazaar statue and you'll end up in a partially loaded Boss Key room. Then shoot the timeshift stone through the ceiling vent. Now if you deathwarp using bombs you'll respawn at the statue you saved at, but the Sandship will be in the past time state, allowing you to continue into the dungeon.
This version is also generally only used combined with unlocking the Captain's Cabin, as it would otherwise be slower than the deathwarp version; in fact, this BiTWarp would not faster than climbing the mast on Japanese versions in those cases; it would only be slightly faster on English versions.
This BiTWarp is however faster if combined with unlocking the Captain's Cabin and shooting the mast target from the bow deck, as it then skips the cutscene of the bokoblins locking the timeshift stone and the doors.
Using the Reverse BiTMagic technique, it is possible to set the goddess crest to be hit in the Sandship. When such a dungeon goddess crest is set to be hit with Reverse BiTMagic, it will cause the cutscene that follows hitting the crest to be started instantly upon loading the map where the goddess crest is. In the case of the Sandship, the goddess crest is in the same map as the boss itself, and as such this allows for completely skipping the fight and obtaining Nayru's Flame immediately.
The corresponding flag is Bx10. On Skyloft it is set at the end of the Batreaux textboxes about the Cursed Medal Chest. Normally you would need 30 crystals to make that chest appear in Batreaux's house and that would work. However using the BiTMagic technique it is possible to make the chest appear early. The scene flag necessary for spawning the chest in Batreaux's house is Bx08, and is usually set either in Eldin by shooting a specific crystal on a wall with the slingshot in the Thrill Digger Cave, or in Ancient Cistern by checking the Statue after climbing the rope. Also, the file that has Bx08 needs to NOT have Bx10. Note that you will also need to use BiTMagic to set 9x04 to unlock the door to Batreaux's house in Back in Time.
The tentacles are most easily eliminated using fully-charged arrow shots; Skyward Strikes should only be used if you run out of arrows. Tentacles will always drop arrows if there are not already two arrow drops on the stage. It takes four felled tentacles to raise Tentalus from the water.
The hitbox on Tentalus' eye is rather strange. Try to set your aim on the top part of Tentalus' eye while it's closed, then shoot as she opens her eye to hit immediately. If you miss, aim again while sidestepping left or right to avoid her attack. It is possible to hit her while she is swinging, but easier to hit her once the strike has landed and her head stops moving.
Once stunned, it takes five strikes to cause Tentalus to recoil. Spin attacks and Skyward Strikes do not do extra damage. Rather than swinging as fast as possible, it is slightly faster to time your five slashes.
Between rounds, you can stand in a corner next to the wall, and no tentacles will be able to spawn underneath you. Then you can pick off the next four tentacles and repeat.
Once you reach the higher deck, shoot Tentalus' eye immediately, then hit her eye five times again until she recoils. Wait a couple seconds and hop into the water. You'll respawn at the other end of the deck, and Tentalus' eye will open as her hydra hair starts to attack, giving you a small opening to shoot her eye again. This shot must be done quickly; it is recommended to use the A button to shoot rather than the quick charge with the C button, as the quick charge takes too long.
If you miss the shot, you can backflip into the water and try again, or just fend off the hydra hair with your sword until you have an opening.
It is possible to completely skip the Scervo fight using Reverse BiTMagic. This trick requires the Practice Sword to have been obtained on at least one file.
The corresponding flag is Dx08. On Skyloft it is set by triggering the Shiekah Stone cutscene near the Sparring Hall. This cutscene can be enabled by saving a file that has obtained the Practice Sword during BiT. Start your file, then run into the trigger to perform the RBM.
This trick is not currently used in All Dungeons speedruns, as it is only slightly faster than fighting Scervo normally, and these runs prefer not to get the Practice Sword. The entire Sandship is skipped in any% runs, so it is not used there either.
The piston section of the Sandship is the most complicated route-wise; with several doors to go through, it can be easy for newer runners to get lost. In addition, there are several small timesavers in this section that can add up.
These are strategies for dealing with the Technoblins in the room with the push-block and the two closed windows.
Upon entering the room, run towards the block and pull a bomb. Start to put the bomb away and roll; this should drop the bomb and allow you to maintain forward movement. The Technoblins will flee from the bomb, allowing you to start pushing the block immediately. After the bomb explodes, the Technoblins will return, but likely not hit you before you finish pulling the block. Even if the Technoblins hit you, you'll save time later by not having to damage yourself as much.
This is the most technical strategy, but also the fastest by about 1 or 2 seconds.
Upon entering the room, run to the block and hide behind it. The Technoblins will lose sight of you and wander back to their starting positions, allowing you to push the block unmolested. This is roughly the same speed as the Bow strat below; possibly slightly faster. It does save two arrows.
The standard strategy is to shoot both Technoblins with charged bow shots. While this is the safest method, it is also slower than the bomb method by about 3 seconds.
After clearing the mast section and going below decks, you can raise the lifeboat to shoot the timeshift stone in the mast. Immediately after the boat rises, you can shoot that eye again; there is then a short delay wherein you can shoot the timeshift stone. This interrupts the cutscene where the boat descends, allowing you to void out and respawn back on the lower deck.
This saves about 3 seconds, but is a little risky; if you take too long to shoot the timeshift stone, you'll ride down with the boat and have to raise it up again.
The ladder leading to the Engine Room usually forces you to climb onto it, then drop. You can skip this by doing a double sidehop and pulling the Sailcloth immediately after.
While this saves a few seconds, it is a little risky. If you don't pull the Sailcloth in time you'll void out, wasting time.
With good movement, it is possible to make an earlier cycle in the piston room belowdecks. This saves about 10 seconds.
The key to this strategy is to run past the ladder before whipping the first post, as that sets your angle back in the direction you need to go when you land.
In the boss key room there's a Beamos blocking a small passage where you're supposed to shoot a arrow. By performing a precise shot it is possible to shoot through it without first destroying the Beamos.
As you need to to activate the timeshift stone anyways, this is arguably slower than just killing the Beamos.
It is possible to reach the area where you fight Scervo from the main deck. Climb the main mast and take the zipline up to the second mast. Drop down to the area of the deck with Nayru's emblem on it; there will be a chain fence there. You can then use a bomb to Highflip over the chain fence and into the partially loaded bow area.
Once you reach this area, you are stuck until you reset or die, since the door isn't loaded.
From the mast that is closest to the bow, it is possible to perform a precise backflip to land in the water without voiding. From there, it is possible to swim OoB under the sandship. Unfortunately, this is too low to do anything interesting.