Ambulator

Ambulators were planeswalking devices first used by Phyrexians. 
==Description==
Using one was an unpleasant experience for mortals, similar to being taken along by a planeswalker. They had two ends, a prime end, and a secondary end, with each end planted on a different plane. Though the two ends functioned differently, the passage they created was two-way.
==History==
Xantcha regularly used Ambulators while she was still working for Phyrexia. When the Mending occurred, all existing planar travel tech, including all existing ambulators, stopped working.Kelly Digges on TwitterMagic Story Podcast: The Mending (May 3, 2018)
===Venser's ambulator===
On Urborg, Venser subconsciously built a machine that mimicked his latent abilities using parts from leftover Phyrexian artifacts.Lynn Abbey (1999) Planeswalker, Wizards of the CoastTime Spiral Cycle Later, a modified version was built with the help of the Ghitu. Since Teferi lost his spark when he healed the Shivan rift, the artifact proved to be invaluable.
In the end, Venser gave the ambulator to Jhoira, since he no longer needed it as a full-fledged planeswalker.
==References==