Making a particle attract to a player

You can set the attractor to work with player positions by setting the attractor to world space (check box) and then make sure you check the box for scaling velocity.

Set the world position of the attractor to an Instance Parameter so you can modify it once the FX are spawned.

In Blueprint retrieve the player world location, and store that as a vector, then pass that vector into the world position of the attractor.

Make sure that the radius of the attractor is large enough to account for the distance from your pawn and emitter actor when spawned. (i.e. make it really massive to test)

This is the exact technique I used for the Zen Garden app we shipped for iOS on iPhone6 when all of the Butterflies flock to your touch input location.