Heal Catalyst Staff GW2 Catalyst WvW Builds
Catalyst strikes foes to build elemental energy and spends it on the jade sphere: a field of your current element, dropped where the squad is, granting boons to allies in it. That is 
Depth of Elements, and it is also what gives the spec its Augment utilities. Two minors ride on top — 
Elemental Empowerment stacks a small buff on you just for being in combat, and 
Elemental Epitome gives you an aura whenever you combo, which is easy when your own sphere is a combo field.
The support build is a boon build, not a healer. 
Spectacular Sphere makes the sphere larger and gives nearby allies quickness and a boon matching your attunement every time you activate it, and 
Sphere Specialist makes those boons last. It runs Giver's and Minstrel's with 
Concentration, because duration is the output you are buying. If the squad needs healing instead, Tempest and Evoker are the ones built for it.
The power build goes the other way: 
Vicious Empowerment, 
Evasive Empowerment and 
Empowered Empowerment turn that little combat stack into the build's damage. It ramps, and it wants a fight long enough to ramp in.
2 Catalyst builds
Heal Catalyst Staff Power Catalyst Spear Playing Catalyst in WvW
Catalyst is a resource spec. Depth of Elements only gives you energy for striking foes, and the sphere spends it — a Catalyst that spends the fight repositioning has nothing to give the squad. Sphere Specialist exists because of that: it lets you keep gaining energy while a sphere is already out, which is why the support build takes it and the damage build does not.
The damage build has the same shape of problem. Elemental Empowerment is a stacking buff and Empowered Empowerment pays the most at the top of the stack, so the build is worth least in the first seconds of a fight and most in the last. Vicious Empowerment and Evasive Empowerment shorten that climb by adding stacks off disables and evades.
So both builds want ground to stand on and a fight that lasts. If the plan is to hit and reset, this is not the spec that benefits from it.