PvP , why 4gate is unstopable ?

On January 16 2011 23:13 Anomandaris wrote:
4 gate is pretty fun and rewards micro.

On January 16 2011 23:13 Anomandaris wrote:
4 gate is pretty fun and rewards micro.

On January 16 2011 23:12 Tone_ wrote:
Gtfo with "I hate 4gate" thread. If it's legitimately a new unposted bug then make a thread around that. No one cares about you making a thread based on your opinions on one build.

On January 16 2011 23:15 frodoguy wrote:

Did you by any chance, 4 gate your way into diamond?
Or did i miss the sarcasm?

On January 16 2011 23:22 TemplarCo. wrote:
well 4gate isn't really unstoppable unless you:
1) don't have enough units
2) try to rush for some high tech
or
3) you fast expanded
If none of this happens really the pylon warp-in thing really doesn't matter

On January 16 2011 23:14 SamGamgee wrote:


rofl what?

On January 16 2011 23:11 Leviance wrote:
Watch White-Ra vs Naniwa game 2 Homestory Cup 2 to see how to defend

On January 16 2011 23:39 Markwerf wrote:
This trick is ages old.

Sure it is easy for P to force themselves onto a ramp through a forcefield. Besides this trick there is also the hallucinated colossus (tramples the forcefields) and the blink stalker rush.
This doesn't mean the forcefield isn't effective.... THe FF still cuts the army in half AND forces the attacking player to warp right in front of the defender's units (which can be easily picked off).

The key to defending a 4 gate is just to not make too many sentries (just 1 or 2) and have some ranged units with that. There are still tons of strats that defend a 4 gate easily (2 / 3 gate robo or dt tech for example).

If there is any problem with a 4 gate it's not the power of the 4 gate but how hard it is to scout imo. For example a FE and 4 gate build have the same build up to the point of the expo really, so if you defend with a 3 gate robo build you still lose to a FE build. DT build is good vs both but then again loses to a robo build and needs to be committed too very early.

On January 16 2011 23:10 Liquid`Tyler wrote:
I've stopped 4gate plenty of times with 2gate robo and 3gate stargate. The force fields are for splitting his army, like force fields are almost always used. And you have a very narrow passage to defend, so you can be successful without superior numbers, because all your units attack simultaneously when an enemy unit comes up the ramp, but all enemy units cannot attack simultaneously, and cannot focus fire.

On January 16 2011 23:10 emythrel wrote:
surely you should be putting your FF on the ramp, not below it. your enemy has vision of the ramp, which means they can warp in on it. if you FF on the ramp they cannot warp in since the FF takes up the space. That way they have to get a zealot up the ramp first before they can warp in above the FF.

On January 16 2011 23:11 AdrenalGBR wrote:
Yep, this has been around for quite some time and I'm sure there have probably been threads on it but people still don't seem to understand how it works (I had to explain it to some guy in a ladder game yesterday).

4-gate can still be defended by other builds in certain situations (cf. forelmashi beating MaNa, TLOpen #8) like if they try and surprise you with it after using all their chronos and not cutting Probes at 16. MaNa also had trouble against ZeeRaX in a recent tournament although he ended up winning that game in pretty incredible fashion.

No seriously, 4 gate in PvP is pretty fun, and rewards good play (micro+multitask+chrono). I dont get why 4 gate in PvP can't be fun.
On the contrary, stupid cannon rushes take no skill and are cheesy as hell.

On January 16 2011 23:33 413X wrote:
Why the hell are people defending this by saying "learn to counter 4gate"? Forcefielding the lower side of the ramp IS the damn counter. If you manage to get that pylon up when just before your warp gates finnish and you don't have 4 gate yourself, u have lost. If you say anything otherwise, it's the 4gater himselfs fault in some way.

On January 16 2011 23:38 MindRush wrote:
just 3 question for you, mister Crappy (the OP)

- Are you the kind of toss who always goes 2/3 gate robo then observer for scouting?
- Are you the kind of player who never attempts to scout unless with 1st scouting probe? (and the only reason he does that is cause he has seen people do this on husky's channel)
- Are you the kind of player who stays with his army in his base and low apm and waits for that damn observer to see what his opponent is doing, and when he scouts the shit, he can't fix it?

If you are one of this things, but SCOUTMORE, for only 22.99APM. SCOUTMORE is a revolutionary product used by progamers, league winners and amateurs alike. Tests show that the proper use of SCOUTMORE benefits agains cheeses, rushes, hidden expos and even map control issues. So why wait? Buy SCOUTMORE today and get free Xel'Naga vision and map information.

On January 16 2011 23:39 REM.ca wrote:
I don't understand what you want patched. I don't see the bug here. Doesn't this work as intended?

I hope you're not proposing that gaining vision of high ground once 3/4 up the ramp needs to be patched.

On January 16 2011 23:54 Dingotrold wrote:
White-RA saw this thread and + Show Spoiler +

On January 16 2011 23:58 Dingotrold wrote:
http://www.readmore.de/index.php?cont=matches&id=32548

Delta Quadrant

On January 16 2011 23:51 Crappy wrote:

Hum , how about click "show spoiler" ?

On January 17 2011 00:17 Competent wrote:
Don't you hate when OPs lie about their rating/league.

4gate is stoppable, there isn't room for argument here, 2 gate robo, simple as that.

On January 16 2011 23:38 MindRush wrote:
just 3 question for you, mister Crappy (the OP)

- Are you the kind of toss who always goes 2/3 gate robo then observer for scouting?
- Are you the kind of player who never attempts to scout unless with 1st scouting probe? (and the only reason he does that is cause he has seen people do this on husky's channel)
- Are you the kind of player who stays with his army in his base and low apm and waits for that damn observer to see what his opponent is doing, and when he scouts the shit, he can't fix it?

If you are one of this things, but SCOUTMORE, for only 22.99APM. SCOUTMORE is a revolutionary product used by progamers, league winners and amateurs alike. Tests show that the proper use of SCOUTMORE benefits agains cheeses, rushes, hidden expos and even map control issues. So why wait? Buy SCOUTMORE today and get free Xel'Naga vision and map information.

On January 16 2011 23:10 emythrel wrote:
... your enemy has vision of the ramp, which means they can warp in on it...

On January 16 2011 23:10 Liquid`Tyler wrote:
I've stopped 4gate plenty of times with 2gate robo and 3gate stargate. The force fields are for splitting his army, like force fields are almost always used. And you have a very narrow passage to defend, so you can be successful without superior numbers, because all your units attack simultaneously when an enemy unit comes up the ramp, but all enemy units cannot attack simultaneously, and cannot focus fire.

On January 17 2011 03:33 AzurewinD wrote:



Did anybody read this? The reigning TSL champ just chimed in with his tactic for stopping a 4 gate and it seems like nobody payed any mind.

No seriously. I just got done reading that, scrolled down, read the following posts, and it seems like everyone just ignored what Tyler just said, continuing with "4 GATE IS IMPOSSIBLE BECAUSE I DO <insert flawed tactic here> AND THEY STILL WIN" without even bothering to develop an effective counter argument to Tyler's approach.

No wonder there's such a hubbub around pros not wanting to read the strategy forums. Nobody listens.

On January 17 2011 03:41 shannn wrote:

There are only few dozens among the hundreds if not thousand of TL posters that reads through all the garbage posts.

I just read Tyler's explaination and I believe he also said something similar when he was commentating someone else's streams on Steppes that the toss could've expo'd since getting out of the ramp had a big advantage for the toss containing the other toss.

This is just a similar case. Tyler's post summed it all up and I didn't bother to read the rest since the rest either agrees or says something similar or it's garbage that does not help people with the problem of defending a 4gate. I don't know how it goes in the sc2 strategy as I haven't been there for 3-4 months now or so.

On January 17 2011 03:09 Backpack wrote:
Anyone who thinks 4gate is dumb needs to stop 14 pooling or going 3 rax. Those builds are too easy and everyone does them.


It's a build, get over it.

On January 17 2011 04:14 traca wrote:
any replays or vods of nony beating 4 gate with 2 gate robo? i remember him pulling this off on hs stream but havent been able to analyse in more details his way to do it

so 2 gate / robo can beat 4 gatebut not 3 gate / robo because you need that immortal asap?

On January 17 2011 03:57 ParasitJonte wrote:


People make a distinction between when something is imbalanced and when something is just stupid/boring.

Tossing a fair coin to determine a winner is "balanced". But nobody would pay to play this ridiculous game. Similarly, people have a problem with 4 gate because it destroys the game.

Personally I don't think that's true on all maps. But on maps like delta quadrant and jungle basin it's just ridiculous.

It's not about balance. It's mostly about having an actual fun game.

On January 17 2011 03:09 Backpack wrote:
Anyone who thinks 4gate is dumb needs to stop 14 pooling or going 3 rax. Those builds are too easy and everyone does them.


It's a build, get over it.

On January 17 2011 04:57 Liquid`Tyler wrote:

You shouldn't make more than 1 sentry imo. They are pretty weak in a fight and it should have energy for 2 force fields, and it only takes 1 force field to split his army, and 2 splits should be plenty. Against that particular 4gate build, I don't think you can mine from 2 gas. There are several ways to do 4gate and several ways to optimally counter. When you are facing this really aggressive, fastest possible 4gate, it's possible that the best counter is to 4gate yourself and wait for your opponent to come up your ramp. Then you're in the classic HuK vs kiwikaki situation from MLG 1, where everyone was like "kiwikaki why'd you go up his ramp" and he says "to attack dude"

When I counter 4gate with 2gate robo, it's when I've scouted a 13gate opening and 2gas. When I scout 10gate and 1gas and saved chrono, I don't make a robo. It's really a danger when you say something like 4gate and think there's only way to do it. Isn't sort of obvious that when I mention 2 ways to stop it that they're for different variations? There's only ever one best way to stop something.

On January 16 2011 23:39 Markwerf wrote:
This trick is ages old.

Sure it is easy for P to force themselves onto a ramp through a forcefield. Besides this trick there is also the hallucinated colossus (tramples the forcefields) and the blink stalker rush..

On January 16 2011 23:10 emythrel wrote:
surely you should be putting your FF on the ramp, not below it. your enemy has vision of the ramp, which means they can warp in on it. if you FF on the ramp they cannot warp in since the FF takes up the space. That way they have to get a zealot up the ramp first before they can warp in above the FF.

On January 17 2011 08:07 rebdomine wrote:


So, is going 4 gates yourself the best way to stop a 1-gas 4 gate?

On January 16 2011 23:10 Liquid`Tyler wrote:
I've stopped 4gate plenty of times with 2gate robo and 3gate stargate. The force fields are for splitting his army, like force fields are almost always used. And you have a very narrow passage to defend, so you can be successful without superior numbers, because all your units attack simultaneously when an enemy unit comes up the ramp, but all enemy units cannot attack simultaneously, and cannot focus fire.

On January 28 2011 02:21 VelRa_G wrote:


Why didn't people just listen to this and stop discussing?

On January 17 2011 04:04 mutantmagnet wrote:
4 Gate is can be deflected but it doesn't help matters much that warpgating emphasizes offense over defense in PvP and the situation will get worse as maps get bigger.

I think it should be considered to revise build timings so warpgate trained units don't train faster than gateway trained units as it currently happens right now.

On January 28 2011 03:44 skipdog172 wrote:


I actually really really like that change. Doubt it'll ever happen, lol!

On January 28 2011 02:21 VelRa_G wrote:


Why didn't people just listen to this and stop discussing?

On January 28 2011 03:49 skipdog172 wrote:
You would think that if 2gate robo is such a great counter to 4gate, they might actually use it and successfully defend 4gates in PvP...but it seems very very rare to see, thus it must be more difficult to hold off 4gates with 2gate robo for them. Clearly they believe that using their own 4gate is a superior response.

On January 28 2011 02:21 VelRa_G wrote:


Why didn't people just listen to this and stop discussing?

On January 28 2011 04:09 Skyro wrote:
And that is the crux of the OP's arguement, and I agree w/ him. On particular maps you have to 4-gate to stop an optimal 4-gate, and to stop it on other maps using a build w/ less gates requires much more precision and micro than the attacking player. This cripples the current matchup by limiting the possible openers you can use to a point that reduces the variation (and IMO, the fun) out of the matchup early to midgame, to an extent that I do not believe was intended by Blizzard because it is not present in any other PvX matchups.

On January 17 2011 03:33 AzurewinD wrote:



Did anybody read this? The reigning TSL champ just chimed in with his tactic for stopping a 4 gate and it seems like nobody payed any mind.

No seriously. I just got done reading that, scrolled down, read the following posts, and it seems like some just ignored what Tyler just said, continuing with "4 GATE IS IMPOSSIBLE BECAUSE I DO <insert flawed tactic here> AND THEY STILL WIN" without even bothering to develop an effective counter argument to Tyler's approach.

No wonder there's such a hubbub around pros not wanting to read the strategy forums. Nobody listens.

Watch his stream sometime to see it in action.

On January 28 2011 04:09 Skyro wrote:


Because it wasn't a complete answer. The *easiest* way to stop an optimal 4-gate is to simply 4-gate yourself and IMO is the *only* way to stop it on maps like DQ and JB where you can warp-in through a backdoor. People who do not rationally think about a person's advice, even if from a credible source, is just as bad as people who ignore said advice.

And that is the crux of the OP's arguement, and I agree w/ him. On particular maps you have to 4-gate to stop an optimal 4-gate, and to stop it on other maps using a build w/ less gates requires much more precision and micro than the attacking player. This cripples the current matchup by limiting the possible openers you can use to a point that reduces the variation (and IMO, the fun) out of the matchup early to midgame, to an extent that I do not believe was intended by Blizzard because it is not present in any other PvX matchups.

So rather than try to nitpick holes in the OP's arguement, or take one person's advice as gospel, see the OP is trying to say, reason things out for yourself, grab a practice partner and practice defending, then come back and contribute something meaningful.

And AFAIK there is no way to use a single FF to prevent warp-ins up your ramp, contrary to what a lot of people are suggesting.

On January 28 2011 04:43 Jermstuddog wrote:


I feel an immense amount of pressure in ZvP to prepare for a 4-gate until I see that my P opponent is specifically NOT doing it. Being caught without enough lings or roaches to at least buy enough time for further reinforcements is game ending. Even if you have the production and economy to outproduce P, there is a 10 second window in there where P can just walk straight through your base unless you completely stop drone production around 25 (some variants require cutting drones as early as 20) in order to bulk up your army just in case.

This seems like pretty much the same thing and it sounds like you think 4-gate should be nerfed in general.

Personally, it sounds fine to me, especially considering all the different variations of 4-gate that are possible. You have 3 units with completely different functions that can be created in different amounts to get the desired effect. 1 gas, 2 gas, pulling probes back off when the desired gas number is achieved. All small differences that should be easily noted by the informed viewer/player.

And it's not like 4-gate is at a disadvantage against 4-gate.

On January 16 2011 23:10 Liquid`Tyler wrote:
I've stopped 4gate plenty of times with 2gate robo and 3gate stargate. The force fields are for splitting his army, like force fields are almost always used. And you have a very narrow passage to defend, so you can be successful without superior numbers, because all your units attack simultaneously when an enemy unit comes up the ramp, but all enemy units cannot attack simultaneously, and cannot focus fire.

On January 28 2011 05:06 Sm3agol wrote:


The thing is...why would you want to stop that? Unless you are MAJORLY skimping on early units, you should be able to rape those units with sentries and zealots with almost no loss to yourself....they have to warp in directly under your fire. Then you have another ~30 seconds before the next group comes. And if you have enough sentries, then you can definitely FF your ramp and prolong this indefinitely for little cost to you and major cost to him. Just don't expect to stop this with a 1/2 gate expo build.....and why should you? That's incredibly greedy.

On January 28 2011 05:15 Skyro wrote:


I cannot speak on the perceived difficultly in stopping an optimal 4-gate as a zerg player as I do not play zerg. I am however highly skeptical that the extent one must go to to stop a 4-gate as a zerg player is close to that of a protoss player who does not 4-gate himself since any protoss player will tell you that there is a much smaller chance of to success to execute a 4-gate on a zerg player (or terran player for that matter) than a protoss player. I think this is also evidenced by the fact that there are still varied openers in PvZ and PvT even though there is the threat of a 4-gate, whereas in PvP there is much less variation (e.g. 4-gating is much more popular), which is the point I am arguing.

On January 28 2011 07:25 Jermstuddog wrote:


It is the same effect in ZvP as it is in PvP. You are forced to stop worker production early and spend money on large amounts of combat units until you have eliminated the possibility of a 4-gate walking over you.

The biggest thing I am trying to point out is that just because you built 4 gateways doesn't mean you have to continue utilizing all those structures every CD available. If you wanted to go 3-gate robo, what stops you from throwing that robo down after the 4th gateway?

ZvZ has this same problem with early tech where getting too many roaches or drones and not enough lings can easily cost you the game if you're caught in the wrong positions. So you are forced to invest in a high number of lings and typically grab the speed upgrade as well for a unit you don't even plan on using in the long term. These lings (and their speed upgrade) don't become useless once you get past that point in the game, you utilize it in a different way later on (runby).

If you're not comfortable going 3 gate vs 4 gate, then fuck it, go 4 gate. Who says this means you can't transition into other builds?

On January 28 2011 05:26 debasers wrote:


I really think that you stopped those people because you're like 10x better. If someone of your level 4gated you, I don't know if you would stop it.

On January 28 2011 08:30 FrankWalls wrote:


its not like the pros 4gate half a minute faster than everyone else lol. an optimal 4gate is pretty simple to do. theres not exactly a lot of deviation someone could do in the situation that would make it any better

On January 16 2011 23:10 Liquid`Tyler wrote:
I've stopped 4gate plenty of times with 2gate robo and 3gate stargate. The force fields are for splitting his army, like force fields are almost always used. And you have a very narrow passage to defend, so you can be successful without superior numbers, because all your units attack simultaneously when an enemy unit comes up the ramp, but all enemy units cannot attack simultaneously, and cannot focus fire.

On January 16 2011 23:10 emythrel wrote:
surely you should be putting your FF on the ramp, not below it. your enemy has vision of the ramp, which means they can warp in on it. if you FF on the ramp they cannot warp in since the FF takes up the space. That way they have to get a zealot up the ramp first before they can warp in above the FF.

On January 16 2011 23:10 Liquid`Tyler wrote:
I've stopped 4gate plenty of times with 2gate robo and 3gate stargate. The force fields are for splitting his army, like force fields are almost always used. And you have a very narrow passage to defend, so you can be successful without superior numbers, because all your units attack simultaneously when an enemy unit comes up the ramp, but all enemy units cannot attack simultaneously, and cannot focus fire.

On January 17 2011 04:57 Liquid`Tyler wrote:
You shouldn't make more than 1 sentry imo. They are pretty weak in a fight and it should have energy for 2 force fields, and it only takes 1 force field to split his army, and 2 splits should be plenty. Against that particular 4gate build, I don't think you can mine from 2 gas. There are several ways to do 4gate and several ways to optimally counter. When you are facing this really aggressive, fastest possible 4gate, it's possible that the best counter is to 4gate yourself and wait for your opponent to come up your ramp. Then you're in the classic HuK vs kiwikaki situation from MLG 1, where everyone was like "kiwikaki why'd you go up his ramp" and he says "to attack dude"

When I counter 4gate with 2gate robo, it's when I've scouted a 13gate opening and 2gas. When I scout 10gate and 1gas and saved chrono, I don't make a robo. It's really a danger when you say something like 4gate and think there's only way to do it. Isn't sort of obvious that when I mention 2 ways to stop it that they're for different variations? There's only ever one best way to stop something.

On January 28 2011 10:07 kcdc wrote:
Has anyone (high masters) tried gas -> gate -> core -> robo -> gate to get a super fast immortal with some zealots and stalkers to support? With 4 chronoboosts, warpgate research finishes 100 seconds after the cyber core finishes, and with 2 chronoboosts, an immortal completes 90 seconds after the cyber core finishes. If you go gas before gateway, you have 200 gas at completion of cyber core (50 for warpgate research, 50 for stalker, 100 for robo). This will delay your gateway and therefore your warpgate research a bit, but you should still be able to get an immortal out before the timing hits. If you can survive the first wave, I'd imagine you could go immortal zealot with your reinforcements and hold pretty comfortably.

On January 28 2011 12:00 FrozenFrotie wrote:
Honestly guys all sorts of 4 gates are stoppable, even the aggressive 20 probe one. It doesnt even require you to do the same build and win through micro.

Im a high masters in SEA server and currently PvP in SEA is pretty much 1 dimensional where everyone goes 20 probe 4 gate with 1 zealot 5 stalkers and try to warp in 4 additional stalkers up the ramp.

I watched a TLO replay where he held it off with a 3 gate tech to dts. Some people didnt give it its due credit because the 4 gate came 1 minute late. However they failed to realize its because tlo tailored his build to counter 20 probe 4 gate almost perfectly.

The general build order is:
11 chrono nexus
12 gate
Chrono nexus again
14 gas
18 gas
Cybercore
Stop probe production
chrono 1st stalker
Build 2 gateways, but make sure to prioritize building the 2nd stalker
Chrono 2nd stalker
Add probes until there are 17 probes mining minerals and 6 on gas
Use the rest of the chronos on warp gate tech
Hunt for proxy pylons and probes - (at this point of time the opponent should be moving out with 1 zealot 1 stalker). Kite the zealot and snipe the stalker. Chase the zealot down back to his base. At this point of the game his will be forced to warp in stalkers in his base to defend against your 2 stalkers.
Warp 2 sentries on top of ramp and retreat with the 2 stalkers.
Build twilight council
Build forge
Build dark shrine
Build 1-2 cannons. (Add stalkers and sentries to make sure you are safe between getting all of these buildings)
Warp in dts and go straight for his probes - win

The essential part to pull this off is good FF placement and micro of sentries. Honestly I find that not many people realize that FF'ing the top half of the ramp blocks vision of the top even when stalkers run up against it. (Unfortunately zealots and sentries which are smaller than stalkers can squeeze into the corner space of the hexagonal shape of the FF and steal some vision of the top of the ramp. But the opponent will take serious damage in the mean time as all of your army can hit them while only part of his army can hit back)

The only way for the opponent to stop this is to go back to his base and get a robo facility for obs. In the mean time, you will already be ahead as you have your 2nd gas up and additional probe count.

On January 28 2011 10:07 kcdc wrote:
Has anyone (high masters) tried gas -> gate -> core -> robo -> gate to get a super fast immortal with some zealots and stalkers to support? With 4 chronoboosts, warpgate research finishes 100 seconds after the cyber core finishes, and with 2 chronoboosts, an immortal completes 90 seconds after the cyber core finishes. If you go gas before gateway, you have 200 gas at completion of cyber core (50 for warpgate research, 50 for stalker, 100 for robo). This will delay your gateway and therefore your warpgate research a bit, but you should still be able to get an immortal out before the timing hits. If you can survive the first wave, I'd imagine you could go immortal zealot with your reinforcements and hold pretty comfortably.

On January 28 2011 12:00 FrozenFrotie wrote:
Honestly guys all sorts of 4 gates are stoppable, even the aggressive 20 probe one. It doesnt even require you to do the same build and win through micro.

Im a high masters in SEA server and currently PvP in SEA is pretty much 1 dimensional where everyone goes 20 probe 4 gate with 1 zealot 5 stalkers and try to warp in 4 additional stalkers up the ramp.

I watched a TLO replay where he held it off with a 3 gate tech to dts. Some people didnt give it its due credit because the 4 gate came 1 minute late. However they failed to realize its because tlo tailored his build to counter 20 probe 4 gate almost perfectly.

The general build order is:
11 chrono nexus
12 gate
Chrono nexus again
14 gas
18 gas
Cybercore
Stop probe production
chrono 1st stalker
Build 2 gateways, but make sure to prioritize building the 2nd stalker
Chrono 2nd stalker
Add probes until there are 17 probes mining minerals and 6 on gas
Use the rest of the chronos on warp gate tech
Hunt for proxy pylons and probes - (at this point of time the opponent should be moving out with 1 zealot 1 stalker). Kite the zealot and snipe the stalker. Chase the zealot down back to his base. At this point of the game his will be forced to warp in stalkers in his base to defend against your 2 stalkers.
Warp 2 sentries on top of ramp and retreat with the 2 stalkers.
Build twilight council
Build forge
Build dark shrine
Build 1-2 cannons. (Add stalkers and sentries to make sure you are safe between getting all of these buildings)
Warp in dts and go straight for his probes - win

The essential part to pull this off is good FF placement and micro of sentries. Honestly I find that not many people realize that FF'ing the top half of the ramp blocks vision of the top even when stalkers run up against it. (Unfortunately zealots and sentries which are smaller than stalkers can squeeze into the corner space of the hexagonal shape of the FF and steal some vision of the top of the ramp. But the opponent will take serious damage in the mean time as all of your army can hit them while only part of his army can hit back)

The only way for the opponent to stop this is to go back to his base and get a robo facility for obs. In the mean time, you will already be ahead as you have your 2nd gas up and additional probe count.