Originally posted by johnpeach249:

usually there is a Burial Chamber in the area. Find it before attacking him then you can nip in and regenerate.

Or just dig under the Elder platform and make a safe spot to dive into when you need a little break. Makes a nice, secure space later on too for an underground base. You can wall it up and make it accessible only via portal, too, and it's a safe room that no raid can get to. Good AFK spot, or place to create a portal chamber, something to that effect.