Starcraft – In StarCraft 2 what function does a referee serve

Guest pass answer for July 2010

When StarCraft 2 was released in July 2010 this was the correct answer:

The guest pass allows a guest to play StarCraft 2 for 7 hours of game time or 14 days from activation (whichever comes first).

Once over a retail version can be purchased.

Guest pass answer for August 2011

As pointed out by marco-fiset things have changed since that time. Now the guest pass gives you access to a "Starter Edition" of Starcraft 2 which gives you the following restrictions:

• The first four missions of the StarCraft II: Wings of Liberty single-player campaign, including Mar Sara 1-3 and the choice to embark on Tychus’s first mission or Dr. Hansen’s first mission.
• The first two Challenges: Tactical Command and Covert Ops.
• Access to the terran race in Custom Games and Single-Player vs. AI.
• Access to the following custom maps (map selection may rotate over time):
  • Xel’Naga Caverns
  • Shattered Temple
  • Discord IV
  • High Orbit
• No map editor.

All campaign progress and earned achievements are saved once you purchase the full edition of the game.

The 7 hour or 14 days time restriction does not apply anymore.

As you go up with difficulty:

• Game speed increases. Brutal is on "Fastest" and each difficulty below that is likewise one speed setting lower.
• Computer AI gets better. Brutal opponents will target your medics first, if possible, for instance, whereas normal and even hard AI opponents will be content to fire at the marines being healed by them.
• AI gets more preplaced units, and attacks with larger groups of units. Example: 2nd Mission: the mineral / gas cache above your start location is unguarded on normal and casual, but on Hard, you've got a marauder and two marines. On brutal, you've got hammer securities and war pigs instead (the stronger, merc versions, of the respective units)
• Some achievements become attainable. No mission achievements are attainable on casual. Normal nets you an achievement for completely finishing (inc. bonus objectives) each mission, as well as a specific achievement related to the mission itself. Hard offers a third achievement, and brutal difficulty is required for the "beat all missions in the campaign on brutal difficulty. (duh! :P)
• Enemies start with upgrades / upgrade sooner
• Numerical objectives may also increase: the number of opponents you must survive on the "In Utter Darkness" mission increases with difficulty (and note that the achievements for this mission are based on kills beyond the mission requirements. The 3rd achievement for "In Utter Darkness" is much easier to get on normal, as when you earn the achievement on normal difficulty, you'll have just slain enough enemies to win on brutal difficulty)
• No change in cutscenes, etc, that I know of.