Long phalanxes involuntarily drift to the right as they advance and charge.
How it works
Hoplites in a phalanx of more than 8 lochoi drift 1 cm (1/2") right on each approach move, and by a rolled amount per taxis during an epidromos. Taxeis drifting farther than the one to their left open gaps; one drifting into its right-hand neighbour is blocked and overlapping lochoi halt behind friends in disarray. Spartan, Theban and mercenary armies may optionally incline 1" deliberately.
Drift: All Hoplites if in a phalanx of more than 8 lochoi, drift 1 cm (or 1/2 inch) to their right each time they move in an approach.