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12-12 Reaper Expand

From Liquipedia StarCraft 2 Wiki
[e][h] Reaper Expand
Strategy Information
Opening, Harass, Scout, Reacting


Opening with a 12 Barracks and cutting one SCV for 50 gas fast enough to build a Reaper; and either a Reactor (for Marines and Bunker to defend) or Reaper (2) to pressure a greedy build that delays ranged units like the Queen and Mothership Core. Either way this is either follow-up with a Factory for Hellions (against Zerg) or 2nd and 3rd Barracks for Marauders and Stimpack research (vs. Protoss)

Info is the Goal[edit]

Reapers are not strong units and require a lot of micro, so it is not necessary to continually harass workers (unless you have the APM. It is much better to scout potential aggression as the strength of the build is being able to take and defend a low-ground expansion (against un-upgraded Zerglings or simply to scout what Protoss makes after the Cybernetics Core.

Basic Build Order[edit]

12-12 Reaper First Fast Expand
  • 10 - Supply Depot
  • 12 - Barracks (1)
  • 12 - Refinery - Stop mining gas after 100 is mined.
  • 15 - Orbital Command Upgrade
  • 15 - Reaper (1)[1]
    • One SCVs off Refinery
  • 17 - Reactor (1) or Reaper (2)
    • Cut one SCV after Orbital Command finishes if Reaper (2), to be able to place Command Center (2) before Supply Depot (2)
  • 17 - Command Center (2)
  • 18 - Supply Depot (2)
  • For Protoss cut SCVs from the Refinery til Barracks (2&3) can be start and then add 3 back to the Refinery.
  • For Zerg, do not cut SCVs from Refinery and build a Factory after Reactor, this way you can have 2-4 Marines for denying Overlords, Bunker, etc.
  1. Replace first Reaper (if it dies) after Reactor finishes


  • Reapers are slower than Zerglings with Metabolic Boost. Bring them back to defend for a more combo with Hellions (1&2).
  • Reaper/s are only useful early game for scouting Protoss, it is not recommended to build more than 1, but 3 Reapers will kill a single Stalker head on.
  • If your opponent scouts your base before you had the chance to finish your Wall-Off be very aware of early pressure/proxies/etc.


Vs. Protoss[edit]

  • Reapers are faster than any Protoss ground units but cannot fight anything convincingly, if your scout is denied do not sacrifice.
  • Follow-up with 2 Barracks for a strong Stimpack timing or Factory for Widow Mines for defense and dropping.
  • Scout for hidden Pylons; attempt to deny these with Marines, but do not bother with getting in fights with Stalkers (which are usually skipped for the rush timing) unless you have a Engineering Bay on the way that can hold at least one mineral line in time for Oracles.



Pro features[edit]

Maps with lots of cliffs, closed off naturals, e.g. Korhal City.

Con features[edit]

Wide natural expansion ramps, very long rush distances, large 4 player maps as this delays and possibly denies your scouting e.g. Whirlwind LE, Tal'Darim Altar.