You need fuel from the flame thrower and the only source of oil are those piranha you see swimming around. Run them down with the boat - one fish fuels one shot. Hurry, you only have two minutes to get all the torches lit!
— Bentley telling Sly how to obtain flame thrower fuel[src]
Sly jumped onto the Swamp Skiff and set out on the lake. The piranhas, the only source of oil for the skiff's flamethrower, swam away as Sly got closer. Using the fuel provided by the fish, Sly lit the 25 local torches within two minutes in order to unlock access to the treasure key.