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Jacob's Ladder is an area used by protoss Templar to maintain their fighting skills. Strategic wargames are carried out with a combination of real troops and hallucinations, and battlefields are chosen to allow the combatants an opportunity to hone a variety of tactical skills. It has also been used for intertribal competitions.
The area serves as a multiplayer map in StarCraft, supporting two players. On the upper land however, choke points are to be found, making defense a more simple matter.
1998-06-12, Jacob's Ladder. StarCraft Compendium Map Archives. Accessed on 2009-07-12