We all remember about the deadmines secret where you blink through the instance portal right? to bad that was patched. i have come on to a secret that lets me do the same with any class.
1) Die infront of instance portal
2)(HARD PART) run into the instance as you are dead but right before you hit the loading screen and get transported back to the GY you res.
3) you will then be behind the instance loading zone and be able to walk around freely behind there....
NOTE* this was tested ONLY on SM instances as of now
im sure this should work with other instances since it is
the same consept