Actually the randomness in this game is not intentional. We could have created towers that have a damage range which creates a random element but we actually wanted this game to be deterministic. Unfortunately that's really hard to do in flash so on different systems and on different runs we sometimes get slightly different results.
Thanks for the feedback.
@Preacher_Txc: This game was created at the Packed games factory which let's you create your own tower defense games (currently in closed beta). It uses the same graphic elements as Gondar TD but has completely different gameplay. We will be releasing more games based on this engine with different maps and themes (fantasy themed game will be released shortly).