Uh oh. I'm in the competition. Guess I better get to work.

There's no chance of having the Decapede ready any time soon, so I bought some stepper drivers off eBay (Geeetech DRV8825) and started wiring them up on a breadboard and connecting them to the AUX pins on the RAMPS. Unfortunately, they did not come with thermal adhesive for the heat sinks.

The only thing the RAMPS needs in order to drive 2 extruders is an additional stepper driver. To run all 4, though, I will need to wire up some extra MOSFETs and voltage dividers for the extra heaters.

On the software side, I'm going to try merging the multiple extruder support from Marlin X2 into Bipolar Marlin. The RepRap X2 is a Prusa variant with dual extruders on independently moving X carriages. It may not look similar to the Theta printer, but from a programming standpoint, this is exactly what I need.