Dimensional Interfacer
A Dimensional Interfacer is a forbidden technology, a device capable of both observing other realities and bridging the gap between them.
Fiction
Timelines
Doctor B has created at least two Dimensional Interfacers. The first time, things didn't turn out well, so he was forbidden to do it again. However, the Cataclysm Survival Treaty designed to combat the end of his universe opened the door to all manners of scientific exploration. With the device, he observed fluctuations in space-time that were causing the end of his reality, originating in the 22nd level. The Interfacer was used to send a party of six explorers into the offending universe to try to better understand the problem.
Later, the Interfacer was used to send additional GoBots to the offending reality.
The Interfacer is both a door and a window, useful for travel, spying and even abduction. The version built by Doctor B could handle only a few tons of matter at a time, though improvements were in the works. The charging cycle took at least a week, and the breakdown in his reality limited its observational capabilities.Withered Hope
Notes

The Dimensional Interfacer made its debut in the Challenge of the GoBots episode, "Invasion from the 21st Level". The Renegades used the device to summon powerful creatures to subdue the Guardians, though they proved unwilling to depart their reality (level 1.)