Ritualist's spirit question (Nightfall)

I have a question about 3 spirits that can be summoned by the Ritualist in Nightfall:

Spirit of Pain- http://wiki.guildwars.com/wiki/Pain
Spirit of Anguish- http://wiki.guildwars.com/wiki/Anguish
Spirit of Fury- http://wiki.guildwars.com/wiki/Gaze_of_Fury

My question is what is the difference between their attacks? What effect do they have on foes? Thanks.

This one cause an unconditional fixed damage.

Anguish cause 2x the damage if the target is hexed

You destroy a target spirit and in place create an allied spirit that cause a fixed damage just like Spirit of Pain.

They cause normal damage and they don't add any effects.