Coral Keeper

Coral Keeper is a casual defense game where you build a deck of sea friends and protect the coral reef. In this vertical mobile game, you merge identical sea friends (crew) to raise their ★ level, hold off waves of sea monsters, and fill your Codex with 24 real crab species.

• Official name: Coral Keeper (Korean title: 산호 수비대)
• Made by: DNICHANI
• Contact: contact@zackson.kr

At a glance

3 core pleasures

1. Place, merge, defend

Place sea friends on the 9 bases around the Reef Keeper in the center. Each turn, 3 cards appear, and you buy them with Bubbles (in-game currency) and place them. Merging identical crew raises their ★ level (up to ★3) and makes them much stronger. If two can't merge, they just swap places, and selling a crew member returns half of the Bubbles you spent.

2. Your combo decides the match

All 28 crew types attack differently. Every enemy has a weakness type such as poison, area, pierce, stun, slow, charge or boss hunting, and crew of the same type deal 1.5× damage. Put Symbiosis pairs that help each other (Hermit Crab + Anemone, Clownfish + Anemone, Sea Otter + Giant Clam and more) on either side of each other and both get stronger. Elites, mini-bosses and two-phase bosses show a warning on the ground before they attack, so tuning your deck and placement to beat them is part of the fun.

3. Collecting and breeding real crabs

The Reef Keepers (your lead crabs) add 24 real crab species to your Codex (the protected Ghost Crab is observation-only and the Horseshoe Crab is event-only, so 22 species can be collected from eggs). Real crabs such as the Snow Crab, King Crab, Coconut Crab, Japanese Spider Crab and Yeti Crab come from eggs, and through ♂♀ Breeding you can raise special individuals that inherit carapace width, color variants (Blue, Golden, Albino and more) and Rage skills. Every Reef Keeper has a Rage skill that turns a crisis around.

What's in the game

• Stages: 10 stages from the Shallow Sandbar to the deep Hydrothermal Vent, each with 3 steps (1-1, 1-2, 1-3). With 3-star challenges and Hard difficulty
• Special: Tide Pool (a short battle 3 times a day), Boss Rush (5 boss fights in a row), Endless Abyss (a record challenge where you keep descending)
• Arena: formation battles against 12 sea rivals (AI) and a Weekly League
• Growth: crew level-ups (up to 10), the Reef Sea Route (a permanent trophy reward path), the Deep-Sea Pass (100 levels), Daily and Weekly Missions, and the Farm (Shells keep piling up even when you're away)
• For details, see the Beginner's Guide, Crew Codex, Game Modes, FAQ and Update History.

Where to get it

• It installs on Android 7.0 or higher.
• The ONE store version has no ads in the app, and instantly grants the bonus rewards you would otherwise get by watching ads. The Apps in Toss version has rewarded ads that you watch only when you want to.

Pricing

• Installing the app is free.
• Paid items (optional): Pearl top-ups, the Starter Pack (₩3,300, once), the Deep-Sea Pass Premium (₩9,900, once), Remove Ads (Apps in Toss version, once), crew-exclusive packs, Reef Keeper packs, limited offers and more. The exact price is the amount shown in each store's checkout window. (Apps in Toss adds VAT, so it can differ from ONE store by a few tens of won.)
• Free reward paths let you enjoy the Stages, Arena and growth content without spending money. See the FAQ.

Age rating

• All ages (self-rated through GRAC, classification number ONIA-SG-261010-0002, content descriptor: Violence)
• Cartoon-style sea creatures fight each other. No people appear, and there is no blood or bodily mutilation. There is no chat or free-text feature.

As of 1.0.17 (2026-10-15)