actually i found other hidden ninja, unused sprites. and would like to know why they weren't implemented and also suggest that as unit.
disclaimer, i dont really know names of sprites, but i remember seeing them.
there was zenith wormhole generator kinda obvious what that be used for,
also there was experimental* ninja cloaked leech star ship *spice things up. it uses very very old leech star ship image but different (longer).
so does any dev care to explain these left out awesome units that could be used as idea in bug tracker?