Board Thread:General Nerf discussion/@comment-27306930-20161111214534/@comment-3362895-20161122113636

The dummies are just to complete the circuit, filling in the empty spaces not taken up by normal batteries (but which you cannot fill with actual batteries because the resulting voltage would be too much for the motors present).

Two ways to get around that:

1) get a custom battery case that holds only the exact number of batteries you need, and wire that into the circuit;

2) custom rewire everything for LiPo instead.