In experimental version 0.8-2435-g705a30b, after getting killed, the KILL COUNT screen does not show any monsters, it said I hadn’t killed any monster yet despite I’ve already killed several zombies.
And a minor bug, not really a bug but the zombie master’s description is too long for the game to show all it all using the " ; " command, this result in a part of the description is clipped off. I suspect other monsters with long descriptions will meet this same fate too.