Slime Castle — Idle TD Game

Contains adsIn-app purchases
67.5K reviews
Content rating
PEGI 7
1M+
Downloads
Content rating
PEGI 7
Mild Violence
In-Game Purchases (Includes Random Items)
Learn more
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image

About this game

The bad humans are invading the mysterious forest! The slime kingdoms in the forest are facing a tremendous crisis!

As a slime chosen by the Slime Sage, you can enhance your abilities through battles, collect legendary equipment, utilize powerful skills, defeat waves of terrifying enemies, and safeguard the peace of the forest.

Once you are defeated, come back stronger!

Slime Castle is a role-playing idle tower defense game.

Players could enjoy an excellent role development system, countless powerful weapons, and several impressive battle scenes.

==== Game Features ====
-Auto-battle system with simple idle clicker gameplay. Enjoy a delightful time!
-Many distinctive maps and different enemies with unique skills. Explore more secrets of this world!.
-Flexible and diverse upgrade system. Build your exclusive fortress!
-Collect mighty equipment and level up the adorable slimes. Experience an extraordinary adventure!
-Abundant free rewards to claim. No need to worry about gold anymore!
-Set battle strategy by combining fortress, equipments, and control enemies. Find the optimal methods to defeat your enemies!

Now let‘s start the epic idle adventure and embark on the path to become the greatest Slime Hero!

Experienced a problem? Got a suggestion? You can reach us at slimecastle@redtailworks.com
Become a Slime Hero! Defend forest against human invasion in the idle TD game!
Updated on
Sep 29, 2026
Available on
Android, Windows*
*Powered by Intel® technology
Events & offers
Featured stories

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
  • This app may share these data types with third parties
    Location, Financial info and 3 others
  • This app may collect these data types
    Location, Financial info and 3 others
  • Data isn’t encrypted
  • Data can’t be deleted

Ratings and reviews

65.1K reviews
Elliot Darnley
March 31, 2026
Been playing this game since September 2024. After all this time the latest update has crippled the stats. Levels I use to be able to idle complete I can no longer. stats have been lowered to a 1/10 of what they were. All that steady slow progress completely undone in one update in the name of balance. More than half of my guild has quit because of this. Well this is how it ends I am done.
9 people found this review helpful
Did you find this helpful?
Azur Interactive Games Limited
April 6, 2026
Hello! We appreciate your feedback on the recent changes. Your insights help us focus on improvements. Thanks for being part of our community!
Geoff Perrett
February 18, 2025
Started off well, satisfying progress etc. I was enjoying so paid for no ads (the ads, although optional do help progress). However, after a while either the developers changed the difficulty or there is some dynamic change to enemies strength which means it is almost impossible to progress. Even going back to levels that you've completed with a much stronger slime become impossible, so you can't even grind out more money to pay for upgrades. Disappointing as I was hoping to complete.
3 people found this review helpful
Did you find this helpful?
Azur Interactive Games Limited
February 25, 2025
We appreciate your feedback and are glad to hear you enjoy the game! The game’s difficulty can shift, but we want you to have fun while playing. If you have more specific concerns, please reach out. Your insights are valuable!
Kostas Moschovas
April 16, 2025
Updating my review due to developer response: My concern is that players who choose to purchase in-game items can find themselves in an unfair situation due to players in other countries who purchase THE SAME THINGS are charged THREE TIMES as much. I don't like paying £92 for something other countries pay $29 for. Other than that, the game is fun for a bit. Very nice artwork & enough complexity. Audio/Music is very low quality, and progress slows to a crawl quickly if f2p. Cheers
4 people found this review helpful
Did you find this helpful?
Azur Interactive Games Limited
April 15, 2025
Hello! Making in-game purchases only speeds up your progress, it's not the only way to get ahead in the game. There are plenty of other ways to earn in-game resources. So, if you're an active player, you can still compete with others. Good luck!

What’s new

1. Global-2 Adventure Card and Slime Skill unlock/advanced mechanism adjustments
2. Removal of the slime mutual exclusion mechanism among Expedition, Pickaxe Transport, and Travel Mode
3. Fixed known issues