The Castle wars rock is used for catapults in Castle Wars. The player may obtain it on the ground floor storage room on a table in either castle. The table stocks unlimited ammo. The rocks are not tradeable and cannot be taken out of the arena as they will be lost when the game is over.
To use this rock, go to a functional catapult located on the corner of the castle wall, left-click on it then move the red x with the arrows to where you want the catapult to hit. The catapult system is criticized for many reasons, some being:
- The inaccuracy of where the rock will go
- Not being able to view where players are on the map (so therefore using more luck than strategy)
- Friendly fire (the rock may hit and kill people on one's own team)
- Not being able to fire near or at the opposing team's castle
Due to these reasons, the catapult system is rarely used, except by players wishing to complete one of the Ardougne Tasks.
Players who have completed Catapult Construction do not get hit by friendly fire.