Blank dimension
According to the Fourth Doctor, a blank dimension was "like a blank sheet of paper...you can write on it, fold it into a 'plane... do whatever you like". Brimo was pulled into a blank dimension when her system's star became a black hole. She created an entire world of anything she wanted using her psychic powers. However, this drew energy from N-Space, the dimension the Doctor was in. The Doctor entered the dimension to stop his universe from being destroyed, plugging the gateway between dimensions with his TARDIS, leaving both Brimo and the Doctor only able to destroy old objects already in the blank dimension to create new ones as they fought one another. When Brimo was exhausted of power, he tricked her into thinking of the Eternity Capsule she was originally trapped inside, trapping her forever. (COMIC: Doctor Who and the Time Witch)