Phalanx formation
Perhaps the best example of the phalanx's flexibility was the oblique advance made in the Battle of Leuctra. There, the Theban general Epaminondas thinned out the right flank and centre of his phalanx, and deepened his left flank to an unheard-of 50 men deep. This reversed the convention by which the right flank of the phalanx was strongest. The new arrangement allowed the Thebans to assault in strength the elite Spartan troops on the right flank of the opposing phalanx. Meanwhile, the centre and right flank of the Theban line were echeloned back, from the opposing phalanx, keeping the weakened parts of the formation from being engaged. Once the Spartan right had been routed by the Theban left, the remainder of the Spartan line also broke. Thus by heading with the powerful wing, Epaminondas was able to defeat an enemy previously thought invincible.