Ok, I found a thread explaining how to get to UC roof, but not how to get to the lvl 60 elite guards without having to kill some abominations, so this is how you do it:
1. swim across the lake, so you end up in southeastern corner of UC
2. go up to the place where the cliff meets the UC wall, and walljump up
3. When at the top, mount up, and jump north
4. When you're at the valley there, run up, northeast, and onto some cliffs where you can walk up to UC wall
5. position yourself right, then jump into UC roof
6. walk southwest, along the edge (where it's no more terrain), until the terrain switches from grass to dirt
7. count the corners on the terrain edge, count three corners, and stand at the next one
8. drink a noggenfogger/cast slowfall/have ice block or blink ready, then jump, and press forward a split second after
9. when you're almost down (if you didn't use SF/noggen), use Ice Block, or blink, so you don't take as much fall damage
10. congrats! you are now on the ledge the bats fly over, just walk left, and follow the ledge until you see the royal guards (60 elite), then just get all guildies to jump over, and pwn them
This exploit don't work for Night Elf, as they are to large to pass step 3 (doesn't work with shrink effect of noggenfogger either), so for Night Elves, i suggest get a warlock and 2 more inside first, then summon
Hope you understood the guide, will get sreens/video soon (banned atm )