This might work on other areas in EotS (such as other "nodes"), but I know for a fact it works on the mage tower. Basically, if you do the "long jump" technique, angling your character at the correct angle you can get on top of the mage tower. This has a few benefits: it counts you as being in range to contest it or keep it from being taken, and obviously makes you a lot stronger in terms of survivability since meleers can't get you. Watch out for shadow step and mind control Here are some screenshots:
http://img251.imageshack.us/img251/7...8231936mv1.jpg
Here you can see the angle I take ... I just do this back and forth up the tower.
http://img210.imageshack.us/img210/5...8232210xi7.jpg
And here is me on top of it, fun stuff!