Area 4

Area 4 is the fourth area of Octo Valley in Splatoon. Agent 3 unlocks this area after completing all missions in Area 3 and completing The Rampaging Octowhirl!, in which access is gained through an Inkrail. It has six standard Kettles and one Boss Kettle.

Locations
There should be 2 Inkrails (Can be found to the left and right) and a Gusher. Take the Inkrail on the left. A Gusher and and extra platforming can be found. Mission 16 can be found on that platform.
 * Mission #16: Propeller-Lift Fortress
 * Location: When first entering Area 4, mission 16 can be found under the area. fall down the large gap you see in area #4.


 * Mission #17: Octosniper Ramparts
 * Location: Upon entering Area 4, Mission 17 can be found on the left side on the front corner of the area. To reach it, there is a Gusher near the Tower. Activate the Gusher and Mission 17 can be found.


 * Mission #18: Spinning Spreaders
 * Location: When reaching Area 4, fall down the large pit, behind Agent 3 is more platform. That is where the kettle is to Mission 18.


 * Mission #19: Tumbling Splatforms
 * Location: (There are 3 ways to reach mission 19 in Area 4)

Option 1: Use the Closest Geyser on the right side of the area, and use the Inkrail to get on a tower. The Tower is actually a pit underground. The Kettle to Mission 19 is on the extra platforms, opposite side from the Inkrail/Propeller.

Option 2: This is the same method for going to Missions 18 and 16, Go underneath the area and use the left Inkrail. Use the Geyser and jump to the Center platform leading to the boss kettle. There is an Inkrail leading to Mission 20, but there's another Inkrail under the Kettle, leading to the same tower to fall down in.

Option 3: Similar to Option 2, after getting off the left Inkrail when fallen in the nearest pit of Area 4, don't use the Geyser. Preform a Squid Jump to the lone platform that holds a single Inkrail. Now Use a sub weapon (Splat Bombs recommended) and throw it at the propeller. The Propeller will head toward the platform Agent 3 is currently on. The platform will take Agent 3 to a platform with the Mission 19 kettle.


 * Mission #20: Octoling Uprising
 * Location: At Area 4, go underneath the area and use the left Inkrail. Then use the Geyser and jump to the Center platform leading to the boss kettle. There is an Inkrail leading to Mission 20.


 * Mission #21: Unwelcome Flying Object
 * Location: Mission 21 can be found on the Tower further away from the entry of Area 4. There are 2 ways of getting to Mission 21:

Option 1: Head to the tower on the right, there should be a geyser underneath the tower and an Inkrail when taken the geyser. Activate the Geyser and fall down the hole. Ageng 3 will be placed to where mission 19 is located, and there is a Propeller-Lift to take. Use the Propeller-lift and it'll take Agent 3 to a lond cube platform with an Inkrail instlled. Use the Inkrail and it'll take Agent 3 above Mission 21. Clip through the grate in squid form and Agent 3 will find the kettle to Mission 21.

Option 2: There is a shortcut to take underneath Area #4, when close to Mission 16, Preform a Swimming Squid Jump to the long Cube platform. Use the Inkrail on the Cube and it'll place Agent 3 above mission 21. Clip through the grate in Squid form and Agent 3 will find mission 21.


 * Mission B4: The Ravenous Octomaw!
 * Location: The Boss Kettle is on a platform in the center that must be accessed via Inkrail.