Spiked Mines

Spiked Mines is the final upgrade for path 1 of the Spike Factory in Bloons Tower Defense 5. It cost $11900 on easy, $14000 on medium, and $15120 on hard. This upgrade rigs the spike balls with heavy explosives. So, the spike balls are set to go off when they lose all their spikes. The explosion sets bloons on fire and pops the every 2 seconds for 6 seconds. Oh, and please feel free to provide more actual information if you're interested.