Shakri cube
From Tardis Wiki, the free Doctor Who reference
The Cubes were cubic boxes used by Shakri in order to confuse the Human race. Each cube had their own features when they were activated for a total of forty-seven minutes after a dormant total time of a year.
Biography
The cubes arrived on Earth overnight and were investigated by UNIT to be found as dormant and unmoving. The Doctor wanted them to be vulnerable, but nothing happened until after a whole year.
