Without any other spells or skills if you move behind an enemy with a decent backstab skill you should do double damage (as long as you hit the target). With Prowl and an unaware opponent you can do a LOT more than 2x damage. I have heard 8x damage and that seems about right from multiple tries with the skill. After having tried prowl with backstab I figured I'd try out certain spells to see if they have any effect on one's backstab damage (expecting certain ones to fail of course). The spells I tried were Entangle, Call Fog, Flash, Stasis, Stun and Invisibility all cast with 100 magickal aptitude. After trying each of these skills about 30 times each I found that casting either Entangle, Call Fog, Flash or Stasis on the enemy did not allow me to do any more than the standard 2x damage. I also tried casting invisibility on myself from a distance wearing elven boots, and other magical equipment with + to noise penalty (supposed to make you quieter, but I believe it only applies to prowl). Invisibility also did not allow me to do more than 2x damage. The only spell out of these that let me consistantly do huge damage was stun, surprisingly enough. I was able to stun enemies, get behind them and usually kill them in a single swing of my blade. Another bonus to stun is that it adds about 30% or so to attack rating. I am not sure if anyone else has other findings, but in general I like to test things out for myself to be sure. Either way, if you want backstab damage, without having to invest in perception and prowl, give stun a try :wink: