A key, under normal circumstances, can only open one door. But if the form of the key changes, then it might open a completely different door.
That was the kind of situation Guding faced.
The original transfer point of the Death Mode of the Purgatory Gate was only fixed at one location, but the remnants of the battle between the Twelve-winged Angel and the Death Saint Knight caused a disturbance in the Time-Space Channel. This changed Guding's original transfer route and sent him to a completely different speck of time-space debris.
Standing on ground covered with lush plants that seemed like a primeval forest, Guding's mood unexpectedly lightened. "I thought the destination would be a barren place; I didn't expect such good greening."