Stakes

Stakes are an ability in the Total War series.

Napoleon: Total War

In Napoleon: Total War, only skirmishers are able to plant stakes. As with previous games, stakes are anti-cavalry devices. When ordered to place stakes, skirmishers spread into a thin line before fixing them into the ground. This process takes about ten seconds, so stakes aren't an option for last-minute defense against cavalry that are close by and charging. Larger regiments of skirmishers can place more stakes. 

Stakes kill any cavalry that run through them in the direction they are facing against, but do little to no damage to cavalry running through them from behind. Stakes break after enough cavalry die on them. 

Stakes are very small on the map and difficult to spot unless close up. Against human players, they can be placed in forests or scrub to further hide them from sight. Stakes can be used on chokepoints (such as river fords or wall breaches) to deter cavalry. 

Stakes act as a weak obstacle to bullets. Skirmishers can use stakes to provide some artificial cover, though this protection goes both ways and weakens their firepower somewhat.