What the title says.

Hello, I'm trying to figure out wand of warding but all it seems to do is stay afloat for 1 turn before shooting a beam at an enemy and then subsequently dying. Am I using it right? Also, if I become a battlemage with it, what does it mean when the wiki says that it will "Heals all sentries on current depth. More advanced sentries get healed more." How is is supposed to heal something that dies in 1 turn and also I haven't seen these "advanced sentries" either. Please help!

Just wondering if a highly upgraded scale armor can carry through the metropolis or if I'm just effed if I don't find a plate armor. If so, what should I be looking to upgrade the scale armor to? Thanks.