How do I cheat to remove an enemy (weretortoise) from my save file?

I normally would be against this, but I just started the game, have no military yet, and no way of walling off the entrance in time to stop it from getting in. I was just going to battle it and see what happens, but then I heard that anyone it bites also gets the curse. There's no way I want to deal with a whole bunch of cursed dwarves ready to pop in my fortress - I don't have the infrastructure this early in the game. So I want to cheat. How do I insta-kill / cure / delete the weretortoise from the game so I don't have to deal with it?

Just to summarise: the WereTortoise has already appeared, and I want to completely remove it from the map

Solution 1:

It's not going to be easy.

As you may know, Dwarf Fortress has no cheating system built in other than what can be done through modding/hacking.

You are probably going to need DFHack. DFHack edits Dwarf Fortresses memory directly and should be able to remove the offending Dwarf. The specific dfhack command to kill a unit is "exterminate". Used with no argument, this command will list all possible targets to kill. An alternative for the sadistic is to use the DFHack command "liquids-here", which will drop 7/7 magma on the location highlighted by your cursor.

Disclaimer: As far as I know, using DFHack is not considered illegal as it has been discussed and distributed on the bay12forums with no negative response from the author.