S.S. Aqua

Fast Ship S.S. Aqua (Japanese: こうそくせんアクアごう High-Speed Vessel Aqua), commonly referred to as simply the S.S. Aqua (Japanese: アクアごう Aqua), is a ferry service that runs between Johto and Kanto.

It is one of the methods of transportation between Johto and Kanto in the Generation and  games, alongside the Magnet Train, walking, and ing or ing. It travels between Olivine City and Vermilion City. A undefined can only travel on this ship after defeating the Johto League.

Voyages
When the player first rides the ship to Vermilion City, a man will bump into them as they board and explain that he lost his granddaughter. When the player first enters the lower deck, a crewman will deny them access to the rest of the ship, asking them to locate a co-worker who is slacking off on the floor above. The crewman is a Sailor in a previously empty room (in Generation IV, the Sailor is found sleeping in a cabin before the player is asked to find him), and once he is defeated in a Pokémon battle, the crewman below will let the player pass. After traversing through the lower deck, the player will find the man's granddaughter trying to get the captain to play with her. The player takes her back to her grandfather, at which point the S.S. Aqua will arrive in Vermilion City and the player can disembark.

After the initial trip to Kanto (which can happen on any day of the week), the S.S. Aqua can be sailed from Kanto to Johto every Sunday and Wednesday and from Johto to Kanto each Monday and Friday. Trips after the initial one will end when the player sleeps in the bed in their cabin, which heals their party.

Trainers can also be encountered and battled on the ship each voyage. In, if the player defeats one or more Trainers on the ship and then boards it again for the same voyage (even on the same day), the Trainers can be battled and defeated again, and the player can keep re-boarding and re-battling the Trainers an unlimited number of times. However, in the Generation IV remakes, once an individual Trainer is defeated, that Trainer can never be battled again, regardless of when or how often the player re-boards the S.S. Aqua.

In the Pokémon Adventures manga
The S.S. Aqua first appeared in Off Course with Corsola, where Lt. Surge unintentionally brought to the ship from Union Cave through a secret underwater tunnel. Soon after, the ship landed in Olivine City, which Crystal, having been in Union Cave to get to the western side of Johto, was pleased to reach. It was also revealed that Lt. Surge tended to use the ship for personal purposes.

In Sandslash Surprise, Lt. Surge used the S.S. Aqua to sail to the Whirl Islands, where and  had wound up after getting defeated by the Masked Man at Lake of Rage. Soon after arriving, the ship was lifted into the air by 's Psychic powers. After Lugia disappeared, the ship was safely brought back down.

The S.S. Aqua briefly reappeared in Epilogue as one of the ships transporting masses of people to visit the. The passengers included the Day-Care Couple, Wilton, Kurt, Maizie, Professor Elm, Joey, DJ Mary, and Hiro.

The ship made a brief cameo appearance in All About Arceus III as one of the locations where Silver and his discovered a Plate, receiving it from the ship's captain.

Trivia

 * In both the Generation II games and, if the player goes to sleep, wakes up, and hears the announcement about docking, checking the Pokégear map will still show the player in the ocean between Johto and Kanto. This is because "S.S. Aqua" is actually a location on the map, and thus cannot change.
 * Like the S.S. Anne and the S.S. Tidal, the S.S. Aqua has one non-player character on-board who mentions being seasick.
 * In, there is a girl in the Olivine Port building who claims that the player has been in Kanto before regardless of if it being their first time there or not.
 * Travelling to either Kanto or Johto in the S.S. Aqua and then ing in the Generation II games causes the player to be taken to either the or  Pokémon Center as opposed to the last Pokémon Center they used in either region, while losing a  sends the player to their cabin. The oddity does not occur when they use the Magnet Train, in which teleporting works as expected. This was fixed in.
 * In :
 * the captain of the ship implies that the S.S. Aqua travels to Sinnoh, as he mentions finding Plates there. However, the ship does not appear in any of the games that take place there.
 * even after the player has obtained all 16 Plates and the Captain hands out Nuggets instead, he still refers to them as "mysterious things" he found from Sinnoh, as if he was still handing out Plates.
 * it is possible to face Georgia and Jeremy in a 6-on-8 Double Battle.

In other languages
M.S. Aqua S.S. Aqua Aquaria M/N Acqua アクアごう 水流号