Battle Tactic: Steel Bow
Arrange two Legion squares in front, with one echeloned back on each flank. (This is a convex formation, resembling a bow, with javelin troops in the center supplying the missles). Place the firing javelins out front at first, but as the enemy approaches, withdraw them behind the protection of the Legion squares who now guard them on three sides. If the enemy tries to outflank the squares to get at the javelins, they will have a long way to go to stretch out over the convex array of squares. The few who manage to siddle around your flanks to attack the exposed rear of the javelins, can be outnumbered and fought off by the javelins alone without any help. If the enemy concentrates against the center instead of scattering around the flanks than the two center legions can hold them while the echeloned flanking legions can move forward, changing the formation from a convex to a concave one and enveloping the enemy flanks. All this will have the support of jevelin fire deployed behind the squares. This was quite successful against 3 full Britsh armies (360 soldiers) although losses were heavy.