Blox Fruits Underwater Island Tips: How to Complete the Hidden Cove Secret

The Underwater Island in Blox Fruits has more to do than just fighting the regular enemies and exploring the area. After the Update 30 Sea 1 rework, the island received several new Secrets, including a hidden cove that is easy to miss if you do not know where to look.

One of the easiest ways to get stuck is the bubble secret. You can see the bubble around the island, but simply walking around it will not explain what you are supposed to do.

Here are the practical tips you need to complete the Hidden Cove Secret without wasting time.

Find the Bubble Area First

Start by exploring the Underwater Island and look for the tall, circular coral formations. The bubble used for this secret is located around these coral structures.

You need to jump over the tall circular coral reefs to reach the bubble area. Once you find the bubble, do not immediately leave the area just because nothing happens.

This is where the secret starts.

The Update 30 secret is officially listed as Ride the Bubbles. The bubble carries your character to a hidden cove where you can interact with a chest and start the next part of the quest.

The Most Important Tip: Stay Inside the Bubble

This is probably the easiest part of the secret to mess up.

Once you enter the bubble, avoid moving around unnecessarily.

Let the bubble carry you instead of trying to control your character as if you were traveling normally. If you move too much and fall out, you may have to return to the bubble and try again.

So, when you get inside:

1. Enter the bubble.
2. Stop moving.
3. Wait for the bubble to carry you.
4. Let it take you to the hidden cove.

You do not need to search for a secret door while you are inside the bubble. The bubble itself is the transportation method.

This is also why this secret can be confusing for players who are discovering Underwater Island without a guide. The entrance does not look like a normal cave entrance or quest marker.

What Happens Inside the Hidden Cove?

After the bubble carries you away from the main part of Underwater Island, you will arrive at a hidden cove.

Look for the hidden chest.

Do not expect the chest to simply give you free loot. Interacting with it starts the combat portion of the secret. The current Update 30 guides describe this as a mob fight that must be completed before the secret is finished.

This means you should prepare for combat before touching the chest.

If your character is already low on health, take a moment to recover first. There is little benefit in rushing toward the chest only to get defeated immediately after activating the fight.

Use an Area-Damage Build If Possible

The enemies that appear during the hidden-cove fight can make the encounter much easier or harder depending on how you approach them.

If you have a fruit, fighting style, sword, or other setup that can hit several enemies at once, this is a good place to use it.

Instead of chasing one enemy around the cove, try to keep multiple enemies within your attack range. This reduces the amount of time you spend dealing with the group.

A simple approach is:

• Activate the chest.
• Move away from the chest if several enemies surround you.
• Create some distance.
• Use attacks that can hit multiple targets.
• Avoid standing still while several enemies are attacking.
• Clear the group before worrying about anything else.

You do not need to overcomplicate the fight. The important part is surviving long enough to defeat the mob.

Don't Leave Before the Fight Is Finished

Another common mistake is assuming that reaching the hidden cove is enough.

It is not.

The chest starts the combat encounter, and you need to defeat the spawned enemies to complete this part of the Island Secret. Once the enemies are gone, the next step is returning to the main Underwater Island area and collecting the quest reward.

So if you are trying to complete the secret for its Island Secret progression, make sure you actually finish the fight.

How to Get Back to Underwater Island

You do not need to spend a long time searching for the original bubble after completing the fight.

The hidden cove has a return route that takes you back toward Underwater Island. Follow the available return point instead of trying to swim or navigate around the map manually.

This is particularly useful if you are completing several Island Secrets in one session. You want to spend your time solving the secret, not running around looking for the exit.

Talk to the Quest NPC Afterward

This final step is easy to overlook.

After completing the hidden-cove fight, return to the main Underwater Island area and talk to the relevant quest-giver NPC.

The secret is not simply about finding the hidden location. You need to finish the quest and collect the reward from the NPC. Current Update 30 guides specifically list the bubble secret as ending with the reward from the quest-giver on Underwater Island.

If you defeated all the enemies but do not see the expected progression, go back and check the NPC first.

Quick Tips for the Underwater Island Hidden Cove

If you only want the short version, remember these points:

Find the tall circular coral formations. They lead you toward the bubble used for the secret.

Do not fight the bubble. Enter it and let it carry you.

Stop moving once you're inside. Unnecessary movement can make you fall out before reaching the hidden area.

Prepare before opening the chest. The chest starts a mob fight.

Use attacks that can handle groups. Clearing several enemies at once makes the fight much faster.

Finish the entire mob fight. Reaching the hidden cove alone does not complete the secret.

Return to the quest NPC. Talk to the NPC on Underwater Island to receive the reward and finish the secret.

Is the Hidden Cove Secret Worth Doing?

Yes, especially if you are working toward completing the Island Secrets added with the Update 30 Sea 1 rework.

Underwater Island has several Secrets rather than just this one. The bubble cove is one, while other secrets involve opening clams, moving crystals to solve a light puzzle, and fighting an Awakened Fishman Lord.

The biggest advantage of the Hidden Cove Secret is that it is relatively straightforward once you know the trick: find the bubble, stop moving, let it carry you, open the chest, defeat the enemies, and return to the quest NPC.

The first attempt can feel confusing because the game does not make the bubble's purpose obvious. Once you know that the bubble is the entrance rather than just part of the scenery, the whole secret becomes much easier to complete.