Game Details 10: Beacons

Ever noticed these strange structures scattered around the battlefield when going through an Arcade run? Perhaps you may not even know they exist? They're known as "beacons" and they are sort of hidden in plain sight. The example shown above can be found at the beginning of mission 5 just before the solar farm.

There is a trick to them, though. They are normally invisible but can be hit by normal shots (which briefly expose their locations). In order to fully reveal and destroy them, they must be damaged by focus shots. What are these beacons exactly? It seems the enemy is using them to conceal and enhance its military operations. That green glow they emit suggest they may have something to do with the crystals that are being excavated from the desert as well.

More importantly, destroying all 18 of them in a single run reveals the true last boss in mission X! Continues are allowed, but they only appear on Arcade difficulty or higher.

With this new intel, good luck and happy hunting!