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Royal Defense: Invisible Threat

By 8Floor

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The castle needs a hero – hordes of trolls are surrounding it!

Build towers, save money, learn spells, and keep the enemy away! Follow the exciting story of the dwarven kingdom's eternal struggle against the troll hordes, who want only to crush the dwarves and claim their territory. To defeat these monstrous hordes, you must construct defensive towers and units and learn to wield powerful spells. Tap anywhere you like for a handy pop-up menu listing all the units and structures that can be built in each location. Tap existing structures to see how you can upgrade your forces with powerful improvements! All your towers and units have specific stats: Damage, Fire rate, Damage radius, Damage type, as well as various other features, such as Enemy Slowdown and Damage Over Time. Each level also brings new units and structures to help you fight the troll menace. You’ll never be lacking for new and exciting ways of decimating those nasty trolls!

What's New in Version 1.1.6

- 10 new levels for chapter V

- now you can build and upgrade towers for gems


iPhone Screenshot 1
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iPad Screenshot 1
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Customer Reviews

Promised extra levels never came

I would give this four, maybe five stars--the IAP cost is high--but what really irks me is that they have been promising more levels for 6 months, but have never delivered. I suspect the company has abandoned this app.

Don't bother

With the newest update now you can use the gems you have to buy with real money to upgrade towers with still now fix to the lack of space to build enough towers to actual survive the 3rd world. I want my money back this game is just a complete waste of time.

Great tower defense

Really solid tower defense game. Lots of levels and plenty of upgrades

Royal Defense: Invisible Threat
View in iTunes
This app is designed for both iPhone and iPad
  • $0.99
  • Category: Games
  • Updated:
  • Version: 1.1.6
  • Size: 150 MB
  • Languages: English, Russian
  • Seller:
Rated 9+ for the following:
  • Infrequent/Mild Cartoon or Fantasy Violence

Compatibility: Requires iOS 4.3 or later. Compatible with iPhone, iPad, and iPod touch.

Customer Ratings

Current Version:
All Versions:

Top In-App Purchases

  1. 300 gems$4.99
  2. 150 gems$2.99
  3. 50 gems$0.99
  4. Unlock Episode 3$0.99
  5. 500 gems$9.99
  6. 1000 gems$19.99
  7. Unlock episode 4$0.99
  8. Unlock episode 5$0.99
  9. Unlock all levels in episode 1$0.99
  10. Unlock all levels in episode 3$0.99