  In this work the properties of minority games containing agents which try to
winning all the time are studied by means of computational simulations. We have
considered several ways of introducing above the rules clever players using
?strategies? which try to outdo the others endowed with statistically
equivalent strategies and compared the resulting behaviours of the ensemble. It
is shown that by introducing such agents the overall performance of the system
gets significantly poorer. While the introduction of a very small fraction of
these never-loosing-players may not destroys the unordered / ordered phase
transition of the standard minority game we find that even for a low
concentration of their presence only a state ?worse? than random coin toss
choices sets in. These special agents/players have the role of impurities or
vacancies in spin systems and their presence may lead to a critical
concentration where the usual phases are washed out.
