On Oldschool the Vasa Crystals all share the same 1 Global time which is 1 minute long.
Whenever Vasa starts moving from the center of the room towards the next crystal, the timer starts ticking. however whenever he is walking from the crystal towards the center of the room the timer is paused (because the next crystal to attack hasn't been decided yet). If the timer ever hits 0 then he walks to the center of the room then teleports you. Then when he starts walking to the next crystal the timer begins again.
I believe your Vasa uses a different timer on every single crystal and that timer resets each time you kill the crystal.