Killing a Siege CS


The great "The Bot Posse" ran into a question about the CS dying in a siege when troops break even. (Yes apparently even we do not seem to know everything)
Two examples below where all the attacking units died as well as the units in the siege. One the CS died, the other the CS did not.

Is this because of the hero maybe? I've always thought if it breaks even then the CS just bounces. If their was no hero and the defense still cleared while all the LS died would the CS have still died or bounced?



not 100% sure but I'd suppose the difference is land unit vs naval unit
I'm pretty sure this happened to me once, all the land units died and but since the attackers myths died as well, the cs was kicked out but not killed
With navy units everything in the harbor dies (except transports)