Caltrops

These actually come in different shapes and sizes, but the basic form is that of a metal ball with four to six spikes or prongs set into it. When a caltrop is thrown to the ground it always lands with one spike standing more or less upright. A thief may throw small caltrops to the ground to slow down pursuers. Caltrops cannot be used as missile weapons, however.

The effect of caltrops depends on how many are thrown down by the thief. The base number is 10 thrown down in an area of 25 square feet. Anyone entering the area must make a saving throw vs. paralyzation. A failed save means that the character has stepped on one, suffering 1d4 points of damage, and must halt movement. If half the number of caltrops is used (only five in a 25-foot area), the save is made at +4; for every extra five dropped in such an area, the save is made at an additional -2 (up to -6 in total). A character moving at less than one-third his normal movement rate doesn't need to make a save. A fresh saving throw must be made for each 5-foot section entered in which caltrops have been dropped.

If a pursuer steps on a caltrop, it must be removed before the pursuer can continue. This takes one round. Also, the pursuer must make a second save vs. paralyzation to see if he is temporarily lamed. If the save is made, pursuit can continue normally. If the save is failed, the pursuer can only move at one-third normal rate for 24 hours (or until the damage is magically healed). An ingenious thief can even improvise caltrops—in one infamous instance, from a sack of potatoes found in the kitchen of a house being burgled and a small bag of nails carried by the thief in question. Modifiers to the saving throws of potential victims can be allowed for such improvised versions!