Top similar games like Rainbow Billy: The Curse of the Leviathan:

Monster Taming RPG about collecting magical computer bugs while exploring Cache Isle!

Monster Harvest is a monster collecting and farming action RPG with a twist! Grow, collect and mutate your crops then take them into battle! Filled with places to discover and multiple ways to build your farm, get ready to craft, explore and battle across the vibrant world of Planimal Point.

Chronomon is a fresh take on the Monster Taming and Farming genre. Catch, train, and evolve unique creatures while rebuilding a world in ruins. Befriend villagers, engage in strategic battles, and grow your farm—all with cross-saves on every device, including smartwatches.

Little Fishing Idle is a relaxing, casual game about capturing and collecting various fish scattered throughout a world inspired by the city of Cambridge. Catch, grow, sell and showcase fish, boosting your store's reputation while idling!

WEBFISHING a multiplayer chatroom-focused fishing game! Relax and fish (on the web!)

Embark on a journey as a rookie angler in Moonglow Bay, fulfilling your partner's final wish. Team up with friends, family, and neighbours to hone your fishing skills, nourish relationships, and restore a remote town's fractured community in this slice-of-life fishing RPG!

Battle teams of Abomis in this turn-based roguelike monster-tamer where the matchups change every run! Recruit creatures from several different indie universes to help close the rifts destroying Abomi Nation. Create your own Abomis or download others from Steam Workshop for infinite possibilities!

Calling all Bounty hunters! Akumi Wars is a turn-based RPG. Build your own party of irresponsible misfit heroes and delve into an epic world story with the ultimate goal of... avoiding needing to work retail. Armed with guns, magic, and a distracting amount of leg, hop on your ship for adventure!

Monster Life is a high degree of freedom role-playing game where you will become a newly arrived monster in Demon King City, embarking on adventures in a fantasy world from a unique perspective, exploring the world, enhancing your strength, and collecting a variety of collectibles.

Search for 100 Jellyfish. A carefully hand drawn 4K scene filled with cute characters. The process is short and won't take up too much player time. You can choose your favorite dyeing for the convenience of color blind players. Extremely easy to achieve.

Necro Story is a creature-collection RPG where you play as a (kind of) evil necromancer more into undead shenanigans than saving the world! Command quirky minions, outsmart foes, and snag their souls to power up your team. Expect strategic combat, laughs, and plenty of mischief.

Battle, catch, and morph hundreds of Fays in this new turn-based creature collector RPG! Traverse the vast realm of The Faylands, filled with bustling cities, challenging dungeons and arenas, hidden routes and unpredictable weather. Ascend ranks to become the ultimate Fay Keeper!

Journey to the vibrant world of Rune Factory and experience the legendary fantasy farming adventure like never before!

Pelago is a creature-catching adventure game! Explore the islands of Pelago and befriend the creatures that live there. Build your perfect team to overcome any challenge and unravel the mysteries of the islands.

A relaxing idle game about fishing. Discover dozens of fishes and treasures! Spend your resources on growing your operation and unlocking new varieties of underground life! Achieve goals, buy skills, and mutate rare fish to improve your profits!

Siralim Ultimate is a monster-catching, dungeon-crawling RPG with a ridiculous amount of depth. Summon over 1200 different creatures and travel through randomly generated dungeons to acquire resources, new creatures, and loot.

Sea Sniffers is a cozy diving game in which you explore the ocean with your trusty seal companion. Encounter strange creatures and exotic treasures in sunken ships or hidden caves. Discover the deep sea and all its secrets!

Fishing Tale is a relaxing fishing adventure game where you catch over 40 unique fish across diverse environments like oceans, lakes, and rivers. Customize your character, track your catches in a detailed journal, and enjoy the soothing sounds of nature.

Cozy Island Idle is a chill fishing idle game where you catch all sort of fantasy fishes to showcase them in an Aquarium to sell them to turn a profit and customize your aquarium and island.

Siralim 3 is a mechanically deep, monster taming RPG. Summon and customize over 700 different creatures to fight for you as you battle your way through randomly generated dungeons. Find rare treasure and use it to craft new items, empower your creatures, learn new spells, and much more.

Bring the corners of your screen to life with CHIMERA CAPSULE, a compact auto-RPG! As a reclusive alchemist, transmute and upgrade a menagerie of goofy minions, and form squads of vibrant monster girls to conquer dungeons in turn-based combat. If making friends is hard, create them!

As the newest ranger of a peacekeeping organization known as SEED, protect your community by rounding up rowdy monsters and going on special missions. Cultivate your farm and friendships alike while unravelling rune-related mysteries!

Battle Fishing Masters combines a fishing RPG and shooter with rogue-lite elements. Catch, battle and collect over 150 unique robot fish. Upgrade new weapons and gear. Meet a cast of exotic characters with quests, and challenge the fishing bosses on your way to becoming the champion!

DRAGON QUEST MONSTERS: The Dark Prince comes to Steam®! Recruit monsters from the DQ series, synthesize new creatures and compose your ideal team.

PIXELS is a turn-based combat roguelike where you battle with and against powerful creatures called Pixels. Fight your way through an ever-changing World where you never know what's next! Recruit Pixels and equip them with items to build the ultimate team! What Team will you lead to Victory?

Little Hooky is a tiny fishing game for a little slack off. if there's nothing to stop you now then, Why don't you play a Little Hooky from work.

Siralim 2 is an old-school monster catching RPG. Summon and customize hundreds of creatures to fight for you as you battle your way through endless dungeons. Find rare treasure and use it to upgrade your castle, empower your creatures, craft powerful artifacts, learn new spells, and much more.

A monster-catching, dungeon-crawling RPG. Delve into mysterious dungeons, capture and train a diverse roster of unique monsters, and unleash them in intense, strategic turn-based battles. Level up your team, discover hidden secrets, and unlock powerful abilities.

Antaria Online is a Cross-Platform MMORPG being developed with community feedback.

In Fishing Echoes, a fishing RPG, you face the elemental forces head-on. Hunt and capture powerful elemental fish to uncover the source of the catastrophic maelstrom threatening your world. Can you unravel the mystery and restore balance before it’s too late?

Fishing game is an itty bitty game inspired by the fishing minigame in Stardew Valley. Filled with a bunch of goofy writing and a handful of spicy gimmicks. Collect over twenty unique fish and add them to your compendium as you navigate through a world of quirky characters and strange locations!

Essentures is inspired by the great games of the 90s and late 80s. You will experience a grand story driven adventure through 4 lore rich kingdoms wherein you can catch and collect mysterious creatures, using them as allies or weapons!

Fish for giant monsters in an epic adventure! Explore Tropical, Arctic, and Lava habitats. Collect your favorite monster fish. Craft the perfect bait. Puzzles and Quests await. Wishlist Today!

Social fishkeeping is back! Tiny Aquarium is a real-time online aquarium simulator. Breed and sell fish, decorate, and visit your friend's aquariums with bite-sized daily sessions.