pretty much where I see it involves 5-6 buried alps then the dreamer uses his abilities to fly where ever he is needed and unburries them using his all his friends trigger...
So you put the alps within range of the target(s) and when they activate they need to take a wp -> 12 with a -3 flip of suffer 1+1+1+1+1 wounds (a wound from each) and get slow... then when they attack they can inflict slow so a severe damage would be 3+1+1+1+1+1 wounds, since its from many sources it ignores hard to kill and the like.
and of course if they kill you another alp is summoned... pretty harsh tactic really, blast weapons are your friends against them since they have only a few wounds each
hope this helps