Circle Defense

I know you have rich experience in defending the Earth!
CIRCLE is a tower defense game with a light card system, where you will play as a commander defending the Earth: by building/upgrading weapons on a rotating device called "CIRCLE" and using cards to deal with the continuously invading aliens.

Origin of the CIRCLE
One day, the moon was hit and destroyed by unknown creatures, and the debris turned into a circle around the Earth. Due to concerns about the unknown creatures, humans transformed the lunar circle into the CIRCLE device and deployed cosmic-level defense weapons on it.

Technology Cards
Under the pressure of alien attacks, the human military technology tree continues to evolve, and its functions are summarized into command cards, waiting for the commander to issue orders.
The energy for the cards comes from the CIRCLE: the faster the Ring rotates, the higher the energy generation rate, but it seems to affect the aiming rhythm for deploying weapons.

Features
- Level-based game: each successful defense against alien attacks will greatly enhance Earth's weapon defense technology, continuously unlocking new weapon types, upgrade items, and new technology cards.
- The combination of different weapon upgrade projects and different cards will create a multitude of possibilities.
- Each type of monster has its own behavior patterns and characteristics, so make sure to respond based on your understanding of them!
- Besides monsters, you also have to face the harsh cosmic environment, and some levels will force you to abandon common strategies to try more suitable solutions.
- You can press the space bar at any time to slow down time for more time to think about strategies and operations; or maybe you just want to see the fireworks in slow motion?