Mercs.. how do I?

How do I get a merc to attack a passive mob? I have caster and melee dps mercs and I can't figure out how to make them attack passive mobs...

You must hit it melee or spell. You can't make your mercenary attack.

If you have a pet you can tell it to attack, and then 'back off' when Merc has engaged.

Also of course range weapons work, or even the Throw Stone discipline.

*edit* Bards have area effect songs that will 'aggro' and cause Merc to engage I think without you being hit even.

Mercenaries will only attack a mob if the mob's most hated (or target) is part of the same group. As others have said, that means it's not possible to tell a merc to attack an unaggroed mob.

Also unless you are alone, the Roles you have set for a group matter.

If you're marked as Puller, the merc will not move from what they perceive as 'camp'.

If you're marked as Main Assist they want to always stay with you and help you with your target.

Mercs won't attack anything that is not on owner's/group's hate list. For example, non-agro NPCs or destructible objects, there is nothing you can do to make mercs attack.

Crap! that's what I was afraid of.

People who hire on glass mercs shouldn't throw stones.