Bluddlust is nice, but its not the uber-spell it once was. If the other team has a human thats decent level I dont bother with bloodlust anymore, breakers counter it hard, you have to bloodlust the other teams army first. At least with walker/docs, they have to have the tier 3 upgrade to fully counter your casters, and they really dont have the mana pool for spell steal AND control magic, even with brilliance aura. You can easily dispel link off their army (well not easily but with good positioning of your walkers it can be done) and recast it on your own, knowing the breakers dont have the mana to steal it again. Plus, spirit walkers can REALLY rip up heavy armor units, their attack is nearly as good as destroyers