TvZ Lagforce’s Mech Opener

General Overview

This Gas First Reactor Hellion opener is a safe way to open into Mech, utilizing Hellions and Widow Mines to stay safe against any early pressure while you build up your midgame infrastructure.

Build Order

  • 10 – Supply Depot
  • 12 – Refinery
  • 14 – Barracks
  • 17 – @100% Barracks, start Orbital Command, Factory, and Reactor on Barracks
    • Pull all 3 SCVs out of your Refinery
  • 17 – 2 more Supply Depots
  • 22 – @100% Factory, swap off onto Reactor and start Hellion production (up to 4)
    • Send floating Barracks to opponent’s base to scout
  • 25 – @400 Mins, start 2nd Command Center and 2nd Refinery
    • Put 3 SCVs back into the first Refinery as well
  • @100% 3rd/4th Hellions, start Widow Mine production (up to 4)
  • @200 Gas, start 2nd Factory and Armory
  • Benchmark: When you start your 2nd Factory and Armory (@6:40ish), you should have 4 Hellions, 2 Widow Mines, and 26 SCVs.
  • @100% Armory, start +1 Vehicle Plating and Tech lab on 2nd Factory
    • Produce 2 Hellions and 1 Siege Tank at a time
  • @100 Gas, start Starport
  • @400 Mins, start 3rd Command Center and 2 more Refineries
  • Benchmark: When you start your 3rd Command Center (@9:10ish), you should have 12 Hellions, 4 Widow Mines, 1 Siege Tank, and around 43 SCVs.


This build has no army production until your first Hellions pop out, so you are somewhat vulnerable to early Zergling rushes.  However, sending an SCV scout out before you start your Barracks at 14 supply will slow down the build a bit, so there’s no good way to scout them coming except seeing them in your main and pulling SCVs appropriately.

All the rest of your scouting will come from your first 4 Hellions.  Use them to poke the front of your opponent’s natural, kill Drones, force your opponent to panic, and spot when your opponent finishes Zergling Speed.  Be sure to be off creep/out of your opponent’s base with these Hellions by the time you see your opponent’s Zergling Speed finish.  Use them later to check for a third base or poke the natural again.


This build only transitions into Mech.  Use your excess Hellions to constantly run in and kill Drones at your opponent’s third/natural while at home you build up your 3 base infrastructure.  Continue your upgrades by starting Blue Flame, +2 Vehicle Armor, and Drilling Claws as you go up to 5 Factories (4 Tech labs, 1 Reactor) and a Starport.  Spend your excess minerals on Hellion runbys, extra Command Centers, and Missile Turrets.

Against Roach/Hydra play, focus on Widow Mine/Siege Tank/Banshee production.  Against Ling/Bling/Muta play, focus on Widow Mine/Hellbat/Siege Tank production (with some Thors added in for extra help against Mutalisk balls).

Pros and Cons

This build is a strong opener to help newer players transition into Mech.  It is also pretty safe against most early attacks Zerg can do because of the early Widow Mines and Siege Tank production built into the build.

However, this build is not quite as economical as a 3CC build such as Innovation’s Reactor Hellion 3CC.  It also is very weak against early Zergling rushes such as a 6pool because it opens Gas First.

Favorable Maps

This build is viable on every map because your scouting with Hellions is largely unaffected by the geometry of a map.

  • King Sejong Station
  • Overgrowth
  • Catallena
  • Merry Go Round
  • Deadwing
  • Foxtrot Labs
  • Nimbus


Lagforce’s Meching to Masters YouTube Example

Lagforce’s Mech Opener Tutorial Replay vs a Very Easy AI


Lagforce on Reddit