The Dragon of The Source Code is the fourth outcome of a software project stored in the text form. This is a bundle of all bad features of the source code and of the correspondent documentation.
The life cycle of The Dragon of The Source Code is very simple. If there is no source code present, this Dragon doesn't exist. The bigger the amount of source code is, the more place to live he has. If the source code won't be used in any way in the future, the Dragon die.
The Dragon of The Source Code creates problems by changes in the source code. He may make the correction of errors and the adding of new features very complex. Sometimes the simplest solution is to throw the old code in a trash can and to write the whole software anew.
The power of the Dragon of The Source Code depends not only on the size of the code. Much more it depends on the quantity and ``quality'' of implemented bad decisions. In our model bad decisions are forced by different Dragons. We may speak The Dragon of The Source Code is a darling of them. He is fed and supported by other Dragons. Well powered and underpinned Dragon of The Source Code can make the software unchangeable. His favourite music is the panicky cry ``Don't touch the code! It works!'' (Of course this decision is initiated by Dragons too and is definitely bad.) 1