Games like Under the blue horizon
Under the blue horizon mostly idle. These games share the most with it, and each one says why.

Desktop FishingDormant
Also desktop companion, animals, ocean · Same active/idle balance (mostly idle)
A frog in the corner of your screen fishes while you work, catching 50+ species with shiny variants and unlocking new spots and outfits.
91% steam90% idle
PC FISH: Taskbar Aquarium
Also desktop companion, ocean, animals · Same active/idle balance (mostly idle)
Raise and breed fish in a desktop aquarium, discover rare traits among 450+ fish and decorations, and trade on the Steam Market.
78% steam90% idle
Ropuka's Idle Island
Also desktop companion, animals · Same active/idle balance (mostly idle)
A frog mows grass in a small window on your desktop; spend the clippings on better tools and island decorations.
97% steam90% idle
Birdwatching Notebook
Also desktop companion, animals · Same active/idle balance (mostly idle)
A small postcard scene on your desktop draws in dozens of bird species as you decorate the spot, unlock new habitats and photograph visitors.
97% steam90% idle
Cornerpond
Also desktop companion, ocean · Same active/idle balance (mostly idle)
A fisherman in the corner of your screen catches fish on his own; sell them for rod and bait upgrades and fill a journal of 100+ species.
97% steam90% idle
Fish to Dish: Idle Sushi
Also desktop companion, ocean · Same active/idle balance (mostly idle)
A fishing boat sits along the edge of your desktop reeling in sea life to serve as sushi, while you upgrade rods and bait and fill an aquarium.
96% steam90% idle
How to Train Your Cock
Also desktop companion, animals · Same active/idle balance (mostly idle)
A rooster idler that sits on your screen and grows from a chick into a muscled bird while you buy hats, decorate his island and compare size with friends.
94% steam90% idle
Tiny Pasture
Also desktop companion, animals · Same active/idle balance (mostly idle)
A strip of pasture along the bottom of your screen where you raise, breed and sell animals for coins while you work.
92% steam90% idle
Maltese's Fluffy Onsen
Also desktop companion, animals · Same active/idle balance (mostly idle)
Run a bathhouse for animal guests at the bottom of your screen, setting bath temperatures, snacks and staff while you do other things.
94% steam90% idle
Not Monday Cafe
Also desktop companion, animals · Same active/idle balance (mostly idle)
A cafe docked at the bottom of your screen where staff cook and serve animal customers, with farm-grown ingredients, 300+ recipes and Twitch chat as guests.
94% steam90% idle
Fishing The Abyss
Also desktop companion, ocean · Same active/idle balance (mostly idle)
A small robot fishes by itself in a tall window beside your work, leveling up to reach deeper water and stranger catches. Clicking helps but is optional.
95% steam90% idle
Idle Waters
Also desktop companion, ocean · Same active/idle balance (mostly idle)
Fish from a window at the bottom of your screen, manually or with auto-fishing, to fill a collection of 100 species across 12 biomes and stock your aquarium.
94% steam90% idle
Screen Cat
Also desktop companion, animals · Same active/idle balance (mostly idle)
A cat roams your desktop while you work; feed it, play with it, and wait for it to bring back collectibles from outside the screen.
90% steam90% idle
Desk Paws
Also desktop companion, animals · Same active/idle balance (mostly idle)
Collect 100+ desktop pets from claw machines, house them for rent, and send them out on trips for materials and snacks.
86% steam90% idle
Little Aviary
Also desktop companion, animals · Same active/idle balance (mostly idle)
Hatch and breed birds in an aviary at the bottom of your screen, sell them for profit, and watch them perch on your other windows.
86% steam90% idle
Capoo Pals
Also desktop companion, animals · Same active/idle balance (mostly idle)
A desktop pet where Capoo and bugcats wander your screen, react to your mouse and can be collected in picture books.
83% steam90% idle
Idlequarium
Also desktop companion, ocean · Same active/idle balance (mostly idle)
Keep a customizable fish tank on your desktop, raising and collecting hundreds of species to earn coins for decorations and new fish.
75% steam90% idle
Fluffy Kitchen Saga
Also desktop companion, animals · Same active/idle balance (mostly idle)
Run a restaurant for fluffy animal customers along the bottom of your screen, earning coins to upgrade and unlock over 50 dishes.
65% steam90% idle
Finn Dorset's Institute For Livestock Replication
Also animals, automation
Clone moon sheep on a dwarf planet, automate wool production and fend off hawks in a hand-drawn cartoon incremental meant to run in the background.
83% steam75% idle
Joyquarium
Also ocean, animals
Raise fry until they are big enough to sell, keep adults in the tank for steady income, and open packs to unlock 144 species. An auto mode lets the tank run on its own.
97% steam70% idle
Shelldiver
Also ocean, animals
An elderly turtle pilots a submarine to catch jellyfish and salvage ocean junk, selling the haul to upgrade gear and dive into deeper biomes.
98% steam
Tuin
Also automation, animals
Tend a vegetable garden with eight crops and farm animals, buying plots, irrigation, and power until the whole farm runs itself.
80% steam70% idle
Plantera 2: Golden Acorn
Also automation, animals
Grow a garden around a magic oak with round helpers who harvest for you, even while the game is closed, and reach for golden acorns.
95% steam50% idle
Plantera
Also automation, animals
Grow a garden of crops, trees and animals while round helpers harvest for you, and keep earning even with the game shut.
89% steam50% idle