A "sarissa" was an 18-ft. long spear used by the Macedonian main infantry unit the "pezhetairoi." It was an advantageous weapon because most other armies at the time utilized a spear half as long as the sarissa. It was this weapon that made it possible to end the era of the Greek "hoplite" warfare. The sarissa had a single iron tip and an iron "butt-spike." The butt-spike would be jammed into the ground at an angle when defending to keep attackers at bay and to provide extra stopping power. The butt-spike also had a practical offensive purpose as well: if the sarissa broke on the battlefield, it did not just become a stick but, rather, two spears. Also, when marching, the butt-spike came in handy to finish-off downed enemies without having to turn the sarissa completely around.
"Boy I'm glad that my sarissa (with butt-spike) is longer than their hoplite spear! Otherwise I'd have had to work to keep those Greek bastards at bay!"
-Macedonian pezhetairoi quoted at the battle of Chaeronea (338 B.C.)