If the Stronghold City on the Continent of Yuantan is considered the "base," then the phase gate would be the "transportation."
For low-level apprentices, the phase gate is of no use. But for any high-end combatant, the phase gate is an escape route. It leads to the other phases of the Abyss, and from there, to the corresponding Wizards' Realm!
In the past, for a wizard to reach another Wizards' Realm, they had to cross decades or even a century's worth of space-time distance.
But if they could leave through the phase gate, they would save a tremendous amount of time!
Even if, as Angel said, a certain price must be paid and a deal struck with Wodell for its use, wizards would still flock to it! Keep in mind that in the past, phase gates were controlled by elite Demon Lords, and humans had no way to touch them!
