Merlin's Gun

In the year 2107 a previously unknown hostile alien civilization captures several planets and interstellar terrian colonies. The Supreme Council of the United Human Nations sends them a warning, threatening to use a terrifying new weapon capable of destroying the whole universe. This ultimate weapon is called Merlin's Gun.
 Alien nation:
 What have you done?
 You're waging war
 That hasn't yet begun
 So we humans warn you
 We've built a device
 We will be sorry to use
 Unless you force us to
 Merlin's Gun (x3)
 It shoots black holes
 And if you force us to
 Oh we won't think twice
 We will use it on you
 At the first strike
 We will end your moon
 And with the second
 We will engulf your sun
 Merlin's Gun (x8)
 The most terrifying device (gun) ever conceived by man
 Merlin's Gun (x8)
 The most efficient device ever built by man to destroy the universe