https://wccftech.com/ratchet-and-clank-rift-apart-guide-where-to-find-the-armor-pod-in-nefarious-city/

Nefarious City is the first sprawling area in Ratchet and Clank Rift Apart, and hidden somewhere is a pocket dimension that holds an armor pod. Amongst the sprawling dark cityscape is a small hole to another world that you can run through to collect the armor pod that offers a permanent buff to anyone that finds it.

Although reaching the pocket dimension is easy enough, finding it is a bit trickier. This guide will walk you through everything you need to do to find the area and collect the armor pod. Be wary ahead for minor spoilers. It's worth noting that while not necessary, it is easy to complete this guide if you have unlocked the Phantom Dash.