You first need to purchase slam dunk trap, then you can both tether and stasis dunk ghost, though stasis dunk was a bit hard for me. What I did was slime tether the ghost to the ground, knocking him out. I would then stasis stream him asap and throw my trap under him. The problem I had with this technique is that the ghost will still slowly drift up into the air after the tethering, so you have to be quick. The most popular tip with Azetlor is use the portals. There is a few portals that will teleport you across the room, and all you need to do is bounce back and forth, boson darting his green eye to take him out. I didn't do this, I just ran about and dodged while constantly rezing Egon and Ray.