Kuragerium

Watch jellyfish drift as idle points build up, then explore the sea to find 120 watercolor creatures. Celebrate rare finds and display favorites in your own tank.

Just watching the jellyfish drift is enough to unwind. Kuragerium is a relaxing sea-life aquarium where idle "observation points" let you explore the ocean and fill a beautiful illustrated encyclopedia. Led by jellyfish, you'll meet 120 real creatures across shallows, deep sea, polar waters, and the night sea.

■ Watch, gather, explore Your tank generates observation points even while you're away. Collect them, then spend them to explore a region — what you'll meet is a surprise until you dive. There are no ads that rush you. Grow your ocean at your own pace.

■ A collection of 120 species Every creature you meet is added to your encyclopedia, with its Japanese and scientific name, habitat depth, size, where to find it, and a bite-sized fact. Around 20 kinds of jellyfish anchor the roster, alongside clownfish, octopus, sea turtles, giant squid and more — each of the five regions (shallows, jelly cove, deep sea, polar, night sea) has its own distinctive species.

■ Rare encounters, special moments Creatures have rarity tiers (N/R/SR/UR); the rarer the find, the more elaborate the reveal — light, particles, and a lingering finish. Meeting a rainbow-framed UR is unforgettable. Tilt a card to shift its shine, and pinch to zoom in.

■ Your own aquarium Arrange your favorite creatures in a tank you lay out however you like. They drift gently through three layers of depth, god-rays, and rising bubbles. New backgrounds unlock as you progress. It's your own little sea, made for watching.

■ Today's visitor A small guest visits your tank each day — from a silhouette teaser the night before to an observation the next day. A gentle daily reason to fill your encyclopedia, little by little.

■ Thoughtful & accessible Comfortable one-handed controls, rarity shown without relying on color alone (frame shape and star count too), support for Reduce Motion, and larger text via Dynamic Type. Everything works visually even with sound off.

■ Premium (one-time) Remove ads, get instant boosts three times a day, keep idle collection running offline for up to 24 hours, save illustrations as wallpaper with a photo mode, and add extra display slots to your tank. It's a one-time purchase, not a subscription, and Restore Purchases is supported.

■ Honest notes ・The encyclopedia illustrations are made with generative AI. They are original watercolor-style art — not photos, and not to accurate scale. ・Every creature featured is a real ocean species. We take the encyclopedia seriously: descriptions are based on facts, and where accounts differ we phrase them as "it is said that…". ・Encounters during exploration are random, but the observation points they cost cannot be purchased (they accrue only from idle time and watching ads). We never sell randomized items. ・Ads appear mainly when adding observation points and on the collection list; watching is optional, and every feature stays usable even when an ad can't be shown.

Credits for audio, illustrations, and data are in Settings > License & Credits.