The Null has been seen in many forms, but the most common form is through red or green crystals that can be viewed with a special device, or eyepiece, in The Room games. However, the only actual representation of it in the show is through its original logo, as well as its time & space logo.
Dino-Weapon
The Null hasn't been prominently seen in contact with Dino-Weapon, but he has been seen to be relatively distant from the Null as a whole, leaning more into Tech and Electric based hardware.
The Gluniverse Crew
The Null and Glue Creatures (as well as Glue itself) have an unusually strong connection to the Null element. There is a chance that Glue and Null are one in the same, but further evidence from the show is needed. However, certain Glue Creatures have eyepieces that allow them to observe Null activity and even have the ability to manipulate the Null to their will.
The main way Null is harnessed is by using a Null Harnessing Device (NHD) to contain crystal or small portions of Null Goop. However, one OOU character discovered a more direct harnessing method. They created the N.E.T.H.E.R. a device which stands for:
Null
Emulated
Transportation and
Harnessing
Endurance
Robot
With the N.E.T.H.E.R., they were able to contain a large Null Crystal for about 3.5 years before certain circumstances forced the N.E.T.H.E.R. to be decommissioned. The result was a battle for control, which destabilized the Null Crystal in the N.E.T.H.E.R. and ended in the explosion of the crystal and the N.E.T.H.E.R. being obliterated. As of September 2022, most of the device has been recovered, but it is not operational in its current state.