Oh weird... in the 40K RTS computer game that still might be one of my favourite games of all time... the Necron's Obelisk was an important building for them (it helped them field more units) but didn't do much else.
But as I was looking this up.. I just found a Dawn of War mod that actually created this exact unit.
Good old DoW1. Yeah the Obelisk does not have a Particle Whip in tabletop. That's a Monolith weapon because of the big crystal it has.