I assume you are being facetious.

I have brained a variety of game, including buff and elephant, but it has to be a near 100% sure shot.

You barely miss the brain on a buff and all you are going to do is piss them off.

It is a great option, but don't blow it. After all the stories of late of the charging heart/lung shot (gut shot?) buffalo, I assume there are few that can pull off the brain shot except under ideal conditions.

Under ideal conditions and 100% certainty, it is the best shot to take. But a "man has to know his limitations."