In Cookie Run Kingdom, there’s a very helpful mode called Tropical Soda Islands. This mode can earn you a steady stream of items. However, it isn’t available at the start, and in order to get it, you’ll need to expand your kingdom.
In order to unlock the Tropical Soda Islands, you’ll have to clear a pathway to the docks towards the West. You’ll have to upgrade your Cookie Castle to level five in order to expand your territory to reach the docks. In addition to that, you’ll have to get the proper materials for expansion. Typically, this expansion will cost you Aurora items and items you can craft from your Blacksmith like shovels and axes. When you finally reach the docks, you’ll need to repair it with two Aurora Pillars, two Aurora Bricks, and two Aurora Compasses. You’ll have to wait 40 minutes for the repairs to be complete. Alternatively, if you find yourself low on any materials or you don’t want to wait, you can use your crystals or earn Aurora-type items through trading at the Seaside Market or at the Train Station.
Once you unlock the mode, you’ll be taken to an ocean that’s covered in clouds. You’ll need Map Fragments and Caramel Spyglasses to clear away the clouds and reveal the area. When that’s done, you can get one of four things: a message bottle, a chest, a Rainbow Soda island, or a regular island conquered by pirates. Message bottles will reveal bits of story, chests will have items like Star Jelly, and Rainbow Soda Islands is necessary to expand further.
A regular island is the most common thing you’ll come across in this mode. As mentioned earlier, these islands are conquered by pirates so you’ll need to complete a battle in order to recapture them. Doing so will give you a steady flow of materials every hour. These materials will be shipped off to your island every 8 hours so be sure to collect them. It’s important to note that these islands can always be reclaimed by pirates, so be sure to check by often to see how your islands are doing.