The sword of contract-Defend country with a sword

Game Description: This is a classic tower defense game, in the magic world, you as an empire will lead your troops to crusade against the desert thieves, but was ambushed, the enemy will attack your base as the tide. And behind was found in the group after the victory over the thief? In the face of a larger crisis, the stronger the enemy will win the final victory?
The game has 4 basic architecture: Tower, tower, turret and barracks mage. Each building can be upgraded, and transfer options. You need to consider how to use limited resources to build all kinds of defensive towers, build in the right place, and upgrade them at the right time.
Game features:
Rich enemy systems make your challenge fun;
The transfer system will give you unique towers bring exclusive skills;
The new talent tree system makes your base defenses more powerful;
Post clearance will unlock more difficult challenges;
At the same time also provides the prop store; can buy many kinds of props to help the player to resist the enemys impact.