Wall of Darkness slows projectiles down and (I think) hides you from view?
Shadow Vortex is like a shadow tornado. It sucks up all units in its path and when it reaches a certain point it “shoots” them in all directions (at least that’s what I think).
Blink teleports your hero to a chosen point 25 meters away AS LONG AS it is in the hero’s line of sight.
Phase Shift makes you practically invisible. You can go through other units and avoid attack, but you can’t go through walls.