Regulon Four

Regulon Four, or Regulon IV, is a planet in the Regulon star system.

"One Shall Rise, Part 3"
In an attempt to escape Earth from Unicron's wrath (and to take command of the Decepticons), Airachnid ordered the Decepticons to set the course for the Nemesis to Regulon Four. Soundwave, however, forcefully objected to deserting Megatron and they remained on Earth.