Hey I was just messing around with Thor and kinda figured out a lot of what goes behind Bassnectar.
Just init a Thor for starts. Take your analog osc and set it to sine wave and drop the octave to a bass frequency. Then enable the shaper and set it to Hard Clip. Play with that Drive knob just for fun; you'll hear that sweet and spicy sound of Bassnectar. But you don't wanna wiggle that thing by yourself; get an LFO to do it for you. Down at the bottom in your routing matrix, send to output from LFO 2 @ -100 to the Shaper Drive. Enable the sync button on at the LFO, then play with the rate knob. You can also play with the Drive knob to find a center range for the LFO to modulate.
Something else I'm experimenting with right now is using a stereo imager to slice the sound into upper and lower frequencies so I can apply a little bit of distortion to the higher frequencies and make them sound a little more dirty, while preserving the lows. This probably isn't exactly how Lorin does it because it's stupid simple but who knows. Works for me