This is my strategry for the medium level 5, Inward Spiral, for the iPhone game GEODefense Swarm.

No Lives Lost:

1. Start with the laser tower at the top
2. Add 6 blaster towers going from the laser tower down to the bottom (3 on each side)
3. Continue adding blaster towers toward the bottom always keeping one more blaster tower on the right side than on the left side
4. Once you’ve built the central path leading to the exit, start building the line of blaster towers from the lower left, around the top and to the lower right
5. Now you can add blaster towers in the gaps and laser towers at the end of the straight paths
6. Upgrade what you can

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