I have a lvl 20 Necro/Monk and i've tried diferent builds. I'll give u some start points.
First u gotta decide if u wanna go full support or u actually want to be part of the hack and slash.
For full support, Blood magic and healing prayers work good toguether with a high soul reaping.
Soul reaping gives u 1 energy per level in that attribute, for anything that dies, and that means, monsters, pets, npc's, minions, party members and ranger spirits. Giving u a almost endless supply of energy. I have even gone as only "healer" with a party that could not find a monk (by that time my monk was only level 5) and kept them all in one piece during the Dragons Lair mission. Constantly casting heal party combined con orizon and word of healing.
For another support u can take blood is power that will give ur party caster a larger regen rate of energy for a period of time.
Curses weaken the mobs greatly, if u can pack em in a block, throw a few curses to them and have and elementalist throw a couple of AoE spells on them... they are toasted.
Death magic is great for having tons of meatballs that will block the mobs for u. So death magic and curses can work good, while mobs are busy fighting ur undead army u can curse em, wrap em, and send em.
Well, u can pm me with any doubts u have.
