I lknow this might be really, really stupid, so I am sorry.
This afternoon I was playing the 4th episode and when I got to the end, I didn't have many weapons, I wasted all the missiles on ravens. So, I tried to beat Devan by putting my 80 something TNTs on his way. His energy was disappearing and then, I expected him to turn into a dragon. But, instead of that, there was nothing! I took a screen capture:

http://www.supersonicsquirrel.net/lj/stuff/end.jpg

Is this normal or is it a bug?

For whatever reason, bosses can be blown off the screen with TNT, and in some cases don't return.

Oh...so there goes my theory of finally finishing B episode when my friend sends me JJ1 again....

Anyway, thanks for help