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The boat is the form of main transport to the different island locations in Chrono Cross. The boat is first gained when Serge and party need to get to the Water Dragon Isle and they go to Arni. It isn't that much use of the boat but the old man by the docks that owns the boat lends it to them for a fee.
Korcha also uses one of the group's boats. Depending on which story path you take when Kid needs the Hydra Humour, either Korcha will give you the boat willingly or his mother Macha will take it from him and give it to you as punishment for his behavior when you give up on Kid. Eventually later the old man by the docks gives you his boat as well for free when you convince him.
When the Terra Tower rises from the sea and into the air, the group needs a way to get to it and so using Starky's ship from the El Nido, Serge and party manage to grant the ability of flight to the boat so it may fly up to Terra Tower.
The boat may be based off the Hawaiian wa’akaukahi (single outrigger canoe).