Yeah, you'll definitely need particles for that. There's no way to do this just with an EFX block, because there you can't tell the laser rays to shoot off in all directions. It's easy to do this with particles, though: just create a spherical emitter shooting off a number of rays, where the emitted ray particles primarily consist of a SNAKE effect. SNAKE is actually better suited for engine trails and the like, but with some tweaking you could probably also create some convincing laser rays.
Here's an example from my "Silvester fun mod" doing something similar:
PARTICLE "colorful explosion"
duration 10
EMITTER
sphere 10
velocity [200,400]
maxcount [50,100]
EMIT
duration 5
position {cont vel e.wind}
SNAKE
Type 13
TextureScale 1
StartRadius 40
EndRadius 50
heatcolor [<1.5,1,0>,<0.25,1,0>] {dur 4.5 lerpto [<1.5,1,0>,<0.25,1,0>]} {intv 4.5,5 lerpto <0.75,0,0>}
Decay 1
Sustain .1
END
END
END
EMITTER
sphere 10
velocity [200,400]
maxcount [400,800]
EMIT
duration 5
position {cont vel e.wind}
SEQUENCE
type #ANI_SPARK
size {dur 2.5 lerp [50,100], [100,200], 0.7}
heatcolor [<1.5,1,0>,<0.25,1,0>] {dur 4.5 lerpto [<1.5,1,0>,<0.25,1,0>]} {intv 4.5,5 lerpto <0.75,0,0>}
END
END
END
END
