Is a non-uniform system of creatures more efficient than a uniform one?

We have analyzed the creatures exploration problem with non-uniform creatures. The creatures' task is to visit all empty cells in an environment containing obstacles with a minimum number of steps. Ten different algorithms with good performance from former investigations were used on 16 environments. New metrics were defined for such a multi agent system, like the absolute and relative efficiency. The efficiency relates the work of an agent system to the work of a reference system. A reference system is such a system that can solve the problem with the lowest number of creatures with potentially different algorithms. It turned out that the system CG-32a (32 creatures, algorithms C and G, alternating placed initially) is 31% respectively 33% more efficient than the reference systems. The relative efficiency was even higher when systems using the same algorithms were compared. Mixing different types of creatures resulted in efficiencies higher than one in 6% of all non-uniform systems.