Cat Hero: Idle RPG is a free-to-play role-playing game developed by Gameduo for Android devices. In this game, you play as a cat hero who is on a mission to save his master from the monsters that haunt his dreams every night. The game's unique gameplay involves merging fish to create stronger fish missiles that will help you defeat the monsters.

The game features a magic tank that constantly replenishes your fish supply, so you don't have to worry about running out of fish. As you progress through the game, you will meet new friends and companions such as Sausage, Onigiri, Chicken, Pudding, and many more. You will also get to explore different areas like Rock Candy Ville and Fish Bone Ruins to find valuable items that will aid you in your mission to save your master. With a big and strong fish and reliable companions, you can conquer the Giant Nightmare and save your master from his fears!