Starcraft – What are decals for in Starcraft 2

I'm not sure if you mean openings or builds, but I'll give you both.

For openings, most Protoss start 13 Gate (9 probes, a pylon, 4 more probes, then a gateway). From here they will usually either build another Gateway or a Cybernetics core. You can go 10 Gate into a 2 Gate rush, but its less common.

There are a number of builds which go down these two routes:

• 1 Gate Expand
• 3 Gate Pressure into Expand
• 2 Gate Rush
• 4 Gate
• 3 Gate into Robo
• Tech into Starport

Since Protoss revolve around gateway units, its common to refer to Protoss strategies by the number of Gateways you build. Its worth noting, that with the exception of 2 gate, all Gateway based builds involve turning your Gateways into Warpgates (Learned at the Cybernetics Facility).

1 Gate Expand is a newer build that has caught on recently (1.1-1.2) with the advent of slower Terran Harassment (specifically Reapers) and more Macro oriented Zerg players. By scouting early and possibly delaying the first Gateway (to 14-ish) the Protoss player can create a much better economy and move to an early expansion. This early expansion allows for much faster gas production and a quicker move to powerful units like Colossus and Void Ray. Though there is an inherent risk in this sort of strategy a very early scout (eg. 8-10) can help make the decision whether to expand after 1 Gate or move to a more solid 3 Gate Pressure build. Liquid`Huk and TSL_GuineaPig are good people to watch for this build.

2 Gate Rush usually involves walling off your Main or your Natural with your first two Gateways and building 5-7 Zealots to rush with. This helps as a defense against any counter rush. This early rush style will later rely on using Warpgate technology to warp in units past that wall. This early rush banks heavily on Zealot's superiority to small numbers of other tier 1 units. This is most effective vs Fast Expand strategies. It also allows for an earlier expansion if you block off your natural.

3 Gate Pressure can involve either an early Cybernetics Core (preferred) or out of a 2 Gate style build. Given the high build speed based around Chronoboost and Warpgates, this build relies on building a very nice tier 1.5 army composed of Zealots, Stalkers and Sentries. This is a very standard opening for most Protoss players as it builds a very powerful army right at the start of the midgame. Try to remember to build Sentries as they are key to this build and Chronoboost your Warpgate technology. The strange part about this build is that it's place in the meta game has shifted drastically. While originally a very aggressive build it has changed to a more macro oriented build allowing the Protoss to use pressure to gain room to expand. Instead of use 3 Gate as a stepping stone to 3 Gate Robo or 4 Gate, a 3 Gate Expand leads to a much stronger 5 Gate + Robo allowing for good mid-game timing attacks.

4 Gate is the natural extension of 3 Gate allowing for a more powerful mid game push (possibly as a follow up to an earlier 3 Gate that was sucessful). This is the logical alternative to 3 Gate into Robo as a Protoss base can support 4 Gateways of continuous production or 3 Gateways and a Robotics Facility. 4 Gate can then move to Robo with the extension of an expansion or move to Templar tech. Templar tech is useful for Terran Bio assisted by Ghosts as the Templar can "snipe" the Ghosts, where as Robo is more effective against Terran Bio or Zerg Hydra/Roach

3 Gate into Robo rose up as a response to early Roach pushes at the beginning of Beta. This usually involved building the first gateway and then immediately teching to Robo before adding on additional Gateways. This provided for the Immortal timing push, which was a strong force backed up by an Immortal. Since the Roach nerfs, and other changes, its more common to build the Gateways first and add on the Robo later as a tech to Colossus. The Colossus gives this strategy an advantage vs Terran Bio or Roach/Hydra Zerg builds. Its also worth noting that 3 Gate Robo gives you an very early Observer which is immensely beneficial.

Tech to Starport builds grew out of early Void Ray rushes. Since those strategies cannot be maintained, a more common move is to instead build Phoenix out of the Starport and use graviton beam to destroy high priced units. These builds usually involve getting a number of Phoenix early and then bringing them along for a 3 Gate timing push. The delayed push is bolstered by being able to remove enemy units from the board. This is especially effective vs Terran Mech. Recently Early Starport has come back into favor with GSL 3. A number of players have been going for early double Starport (especially in PvZ). In addition to the early Phoenix for harass, they've also been adding in Void Rays. Void Rays were traditionally only a strong unit once charged, however, in patch 1.1.2 the uncharged damage was buffed. As a result Void Rays became much stronger both early in engagements and once they had reached large numbers. This combined with many Zergs relying heavily on Roaches after their range buff (also 1.1.2) lead to many more Starport centric builds.

Finally, it is worth noting there are a number of cheese builds. These revolve around hiding a Dark Templar shrine or Starport for Void Ray. While they are not sustainable builds, they are worth mentioning.

Note I use the terms:

Tier 1 to indicate: Zerglings, Zealots, and Marines.

Tier 1.5 to indicate: Stalkers, Sentries, Roaches, Banelings, Marauders, and Reapers.

Certain units are better at scouting than others, but you should always scout constantly. There are a couple units which work well for scouting:

• Early worker -> a definite must, usually at ~10 supply, but if you think you can do it around 12-13, even better
• Tier 1 units (marine, zergling, Zealot) -> they're cheap so suicide them into your opponents army to see what he has been building
• Air scouts (Overlord, Observer) -> you may have to sacrifice these for intel, so I suggest you place one at the top of the opponents main, and one at the bottom. This way you can move in and quickly see his entire base
• Terran specific (Orbital Command and Flying buildings) -> I actually recommend building an extra barracks and flying that in to scout. It has a lot of HP and should see plenty. Also, every MULE is worth 50 energy and gets you 250 minerals. Usually a better use of 50 energy than a scan (though not if you need to see invisible).
• Protoss specific: In the expansion Heart of the Swarm hallucinate no longer needs to be researched and is a fantastic way to scout. Hallucinate a phoenix and fly it where you want to scout.

Goals of Scouting:

• Scout a build order (opponents starting production) -> When did he build a spawning pool? Did he go 2 Gate or Cybernetics core? Techlab on his Barracks or Factory? These will help you deal with early agression
• Scout attack forces -> Knowing when an enemy is coming is vital. The more time you have to prepare the better. Place a unit near his ramp and control those watch towers if you can!
• Scout composition -> Knowing mid/late game what your enemy forces look like, will allow you to better adapt. Lots of Roaches? Build some immortals. Tons of Marines? Morph some banelings. Colossus? Vikings!
• Scout expansions -> leave some Tier 1 or spare units at various expansions on the map so he doesn't sneak in a free base.

When to Scout:

• Constantly
• Always
• Every chance you get
• NOW!!!!

There is never a bad time to scout.

Note: I would caution against assimilator trick. While it is slightly better as protoss than other races, you are essentially wasting resources and forcing him to play a more Tier 1 focused and aggressive strategy. If I only have minerals I'm going to build a lot of Gateway/Barracks/Hatcheries and push out cheap units instead of teching. Not a good position for my opponent who had to sacrifice 150 minerals.