Need help dealing with Sidhe Lords

[Psycho]

Don't empower. Send along a thaumaturg to cast luck and body ethereal on your thug.

Depending on how sidhe lords are equipped you have a variety of options. If they spam thunderstrike they will tire eventually, so good old skellyspamming will take them out in the end. For wraithlords just script soul vortex. That will take them out in the end and focus your equipment on staying alive. You can also do drain life with grand thaumaturgists or give standard of the damned to a thug. It should take them out in two shots (first one takes out mistform).

Also, mind hunt them. That spell kills them even when they hide.