Tzim-Sha travelled to Earth in a pod-like spaceship.
The craft landed in a Peak District forest and was initially discovered — and touched — by Ryan Sinclair. He quickly learnt that the exterior hull of the pod was exceedingly cold, and he pulled his hand away immediately.
Unbeknownst to him, however, touching the pod was a contractual act in the eyes of the Stenza warrior within. It signalled to Tzim-Sha that humans accepted the conditions of his hunt for a particular person — a precondition to achieving leadership of the Stenza.
After touching the pod, Ryan almost immediately placed a 999 call, and Sheffield police officer Yasmin Khan responded to investigate.
Later, when Ryan and Yaz brought the Thirteenth Doctor back to the pod's landing spot, they — along with Graham and Grace — discovered it had been taken away by Rahul and Andy who were investigating the disappearance of Rahul's sister. Like Karl, Rahul's sister had also been prey for an earlier Stenza hunt and Rahul surmised the pod was somehow connected. For a time, he had the pod under constant video surveillance.
Eventually, though, Tzim-Sha exited his pod and killed Rahul. When the TARDIS travellers arrived, the pod was apparently broken beyond repair. Nevertheless, the Doctor was able to salvage some of it to construct her new sonic screwdriver. The Doctor retrieved the pod's Stenza recall device and used it to send Tzim-Sha off of Earth. She later used some of its other components to teleport to where her TARDIS was located. The pod thereby became an integral, if subtle, part of that incarnation's life. (TV: The Woman Who Fell to Earth)