zainale wrote:
to create a Roman shield wall?
You can't. Roman shield walls are designed with real combat in mind, which D&D doesn't do. The abstraction of AC to "hit" or "miss" means that literally overlapping your tower shields and hiding behind them means almost nothing to a more powerful individual foe - human or otherwise. Pathfinder is particularly bad since BAB goes from 0-20 and buffs make that grow even greater, so the bonus AC gets lost in the math of the game.
The best way to model this as a GM would be using swarm rules for a group of humans, and giving the shield wall DR or concealment. As an individual player, the best way to model the tactical function is to cast a fog spell and force enemies to fight into the concealment at the border of the fog.
EDIT
In terms of systems modeling this from a HEMA perspective, they normally allow shields to flat block incoming attacks against a portion of the body and allow a shield wall to cover bonus portions of the body so they are even harder to land a blow on. That's why concealment (a flat miss chance) makes for a decent model of the tactic.
