Merge Crystals: Protect Front Line

Welcome to the Idle Tower Defense world of Protect Front Line!

Merge the crystals and protect your front line!

Click your Level 1 Crystal to the other to merge a Level 2 Crystal.

Merge your Crystals to a higher level and move your Crystals to the Turret Grids fight against the Zombies.

It will be a challenge for you when your reach higher levels.

The Tower Defense game (TD) is endless - fight against infinite number of waves for as long as you can!

And we will offer more exciting FREE events for you soon！