Grow and expand the land with air, aiming to rebuild the undersea city with a lone girl, Hele! A new type of undersea city-building simulation game!
Grow land and build a city!
Build your own undersea city with Hele!


This game is a simulation game that takes place on a wide ocean floor, where "land" is cultivated and "cities" are built!
This is an undersea city-building simulation game set in an undersea city that has lost its people, where you and the main character "Hele Tokitsumi" aim to restore the city.
The goal is to expand the city by utilizing air-generating structures called "Mira's Flowers" and cultivating the surrounding land,
The goal is to restore the original vitality of the city.


Buildings consume "air" to operate,
Air must be produced and supplied by a plant called "Mira's Flower."
In order to plant "Mira's Flowers," the land must be cultivated.
In order to raise the land grade, it is necessary to acquire a "prosperity value".
The "fertility value" can be obtained at random from the land around the facility when the residents use the facility,
When a certain amount of "thriving value" is acquired, the land grade will be raised.
There are several types of Mira flowers, each with different characteristics, so the key to the strategy is to develop the city while utilizing various Mira flowers according to the environment and progress.


Each of the more than 50 buildings in this title is classified into four types.
"Dwellings," which allow residents to call a town home,
"Production facilities," which can be set up around special terrain where resources are buried, and where residents can obtain resources when they visit,
"Processing facilities," which can earn money in exchange for resources,
"Commercial facilities," which residents can use to earn money.


Exploration is required to obtain recipes for new buildings, Mira's flower seeds, mysterious oparts needed to liberate the story, and area liberation items.
The objective is to board an exploration boat and wade through enemies and traps that lurk in the deep sea to obtain the items and to step over them.
There are three parameters for exploration boats: HP, air, and payload, each of which can be strengthened with money.


In this title, including the main character Helle,
More than 30 different characters will enliven your town with their dot-pictures.
Some of the inhabitants are cute animals...?
Please look for them!


In addition, there are three difficulty levels in this game: [EASY], [NORMAL], and [HARD]!
There is also an EASY mode for those who are new to city planning games, and a NORMAL mode for those who have played many city planning SLGs,
The game also offers three difficulty levels: EASY, NORMAL, and HARD!


You and Hele will weave a story that is well worth reading!

The setting is the underwater city of Garden, where the sky is covered by the sea.
In this city built by the ancient people who escaped from the fire-engulfed earth long ago, the "Mira Flower," which produces air, sustains the lives of the residents,
The "Mira Flower," which produces air, supports the lives of the inhabitants.
The disappearance of Yona Kujira, the person in charge of governing and managing the Garden, has left the city in ruins,
The "Sengu," a Shinto ritual in which the city is rebuilt from the ground up once every 150 years.
The effects of these events caused many residents who had been living peacefully in the Garden to flee to other underwater cities.
The only one in the undersea city that has lost everything, buildings and residents,
Hele Tokitsumi" is struggling to bring the city back to life.
In the midst of all this, the player, transformed into a stuffed sheep, is sent to the Garden by chance,
The player, disguised as a "stuffed sheep," is sent to the Garden by chance.
Together with Herre, you and Tokitsumi will work together to make the Garden a great town again!

// Option A //

To download Helle's Undersea City Project mod from HappyMod.com.
You need enable the option "Unknown Sources".
1. Click on the above link to download Helle's Undersea City Project mod APK.
2. Save the file in your device Downloads folder.
3. Now tap on Install and wait for the installation to finish.
4. Once it is done, open the game and start playing it right away.

// Option B //

To download Helle's Undersea City Project from HappyMod APP, you can follow this:
1. Open your browser and download the HappyMod APK file from HappyMod.com - the only official website of HappyMod.
2. Open Android Settings and go into Privacy or Security.
3. Tap the option to Allow Unknown Sources and enable it.
4. Go to your Android downloads and tap the APK file.
5. Follow the directions on the screen to install it.
6. Search Helle's Undersea City Project in HappyMod App.