ProtoDeuteric / Solution One

Black first.  

Because of my blind spot at S1, This is the sequence that I read out. Obviously not more than strictly a beginner exercise. Notice that after , white is already dead.

Black first.  

maruseru: This also works. is a bulky-five nakade.

Black first.  

It turns out just in this diagram is sufficient. If white connects at a, it will be a bulky-five nakade again. And white b is self-atari.

Black first.  

unkx80: kills too.

Black first.  

This also kills. Seems like this is a good "how many first moves" exercise. ;)

Black first.  

ilan: Seems like this works as well. Speaking of which, I've been trying to find "most inefficient kills" when observing Tsumego lessons on KGS. I've also noticed in some of these lessons that strong players have "bad move blindness" analogous to weak player blindness, except that they overlook unobvious inefficient moves.