[G] PvZ FE to Void Ray

The problem with it is that it is basically a rush strategy and zerg is excellent on putting on pressure. If the zerg puts on too much pressure, and delays your teching while also teching himself, he can be on even footing or even beat you.
It also suffers of a weakness from backdoors and requires you to be able to defend your main and your natural with the same cannon line.
You are going to have difficulty scouting as you have no observers and handful of speedlings can deny any scouting probe or stalker, so you must make the most out of limited information. Many times reaching his base with your army will be the initial contact with his army and you will have to react from there.
Because you have a small high-tech army it can only be in one place at once, so you will have to rely on static defenses, and later, warped in units, to defend your bases, sometimes you may even have to pull probes.
Also because you are FE, any weakness of your FE can be exploited.

You do the fastest PvZ FE, so use whatever tricks you know. My current strategy is to scout for his pool, put down a forge when you see his pool and then a Nexus on 21, or a Nexus on 17. Put down 2 cannons to start, three if he goes gas pool. Your first cannon should defend your ramp, your second should prevent zerglings from hitting your nexus, and the third should prevent zerglings from hitting your assimilators while covering another cannon.. All your cannons should be in range of as many other cannons so that 2 cannons will hit any zergling attacking a cannon. Build a gateway ASAP, before your third cannon if possible, then scout him while building 2 assimilators in your main. If you see a mass of zerglings or roaches, get more cannons. If you see banelings try walling off your cannons with more gateways or getting sentries for forcefield. If he's just building drones just build 2 more assimilators and a cyber core. Keep pumping probes, Void Rays are expensive and you need the minerals in case your rush fails or more cannons are needed. It's not an all in if you do it right.

Try and scout his base to see when he gets gas and a lair. A fast lair means a fast nydus, one gas means roaches, more means hydra/muta. If he has a lair is pretty hard to tell. Lairs morph faster than zergling speed, so there's no way to know if he has a lair but to go see it for yourself. If you can't see if he has a lair you have no choice but to patrol your base for a nydus worm. If you see one you have to kill it with your probes or you are dead. The earliest a nydus worm can appear in your base is when you are starting your stargates. So you won't even have a zealot in most cases, and he'll have no units to scout - a single round of larvae injects of roach and zerglings in a nydus is enough to kill you.. so scout his army like your life depends on it and make the minimum number of cannons needed to live or else.

As soon as your cyber core finishes you should start the air weapons upgrade. Then look at your gas. If you have ~300 gas then start building your stargates, you should have enough for 3 of them by the time you get your first 2 down. If you have more, try and consider how much extra gas you have. If you have over 700 gas you should probably get 4 stargates. If you have more. you should get some sentries (guardian shield <3) and strongly consider abandoning this build. But if you insist, you can get a fleet beacon and then shield upgrade from the forge. If you have extra minerals, build a zealot and some more cannons or try and sneak an expand.

Once your stargates are done build 3 VRs and start saving your chrono boost. If your stargates are scouted, immediately attack with them, otherwise, wait for another 3 VRs to attack. Use all your chrono boost on the second wave of VRs, then chrono boost out more phoenixes. Try and time your attack so your VR and phoenix arrive at his base at the same time.

The third: If he took a fast third in response to your early expand kill it off if its in your way, otherwise just ignore it.

You have basically two strategies here: Kill off his expos so that you can get a economic advantage, or go to his main and kill off any tech so he can't make mobile units so you can get the economic advantage. But its not good enough to kill just one expo, he has to be reduced to one base vs your (soon) three bases.

So if his natural is in your way, feel free to blast the drones, but strongly consider going into his main to get the anti air tech.

Now you've done it. The Zerg is probably screaming about imba right now, but the fact is, that he can destroy all your units for cost or force you to fall back. The only reason he won't is if he failed to scout, and he had overlords. So here's how to make it works.

First bring a zealot along with your army. Your VRs will protect it against any speedlings. When you get near him send in the zealot first. If you're lucky the zealot will see what units he has.

The most dangerous case is mass muta; you need to pull back and wait for 6 or so phoenix or you will lose all your VR!

Best case is mass roach or zergling/baneling or a ton of spine crawlers, but many Zerg players will not even attack your base with any ground army, trying to hide their hydras in clumps of roaches so you can't micro them down or just too focused on microing their anti air.

Spore Colonies or Hydras mean you have to fall back and tech to carriers and +3 air damage. Get a third base and 4 warp gates of zealots while you store up gas to make your first round of carriers.

Mass queens is easy, just get more phoenix, then lift them all up for a GG,

A mix of say, 6 hydra 3 queens and 8 muta will be very deadly, since they will kill all your VR for sure and you won't really be able to run because of the speed of muta and hydra on creep.

If you're in his base killing his stuff while his army is streaming in, its important to know what to target first.

1 HP spore colonies are a given, since once they finish they'll be able to push you off, and killing them outright means less minerals for him to make hydra or queens or more spore colonies.

Also scare away the drones if you can, a second of 6 VRs blasting at drones will usually be enough to maynard them to the natural so you can get on with blasting the base, but if he wants to let you kill his drones, more power to him. You don't want to chase them but its best(?) if they run away.

The next is a hydra den; you can handle pure spire tech with vr/phoenix. But with hydras mixed in you are going to be out of luck and you won't be making colossus neither.

Overlords: Killing ovies is great way to start a battle, so that he can't use all his saved up larvae to kill you. But if you can't find his ovie swarm before you kill his drones, don't bother until now.

Then the spire. If there's just one evo chamber and all 6 of your VR are alive, go ahead and kill it off now too, otherwise head for his natural and kill all the drones there.

If he's just got an evo chamber and has built a ton (more than 5) of spore colonies that are actually all clustered around his hatchery and not so you can just take damage from one at a time, just fall back and do a 12 warp gate to finish the job.

You may not be able to retreat but you should try. This is a very expensive little army, representing 2000 minerals and 900 gas. If you have to run away and hide in your cannons that's fine, you shouldn't die yet as long as you remember to expand. Your reaction should vary depending on his build.

Too many hydra: Time to get a third and go carrier/zealot. If you have good macro you can have so many zealot that they will all die and none of your carriers will.

Mix of hydra/muta: You'll need to keep going VR/phoenix but need a third base to get some high templar along with gateway units. That's because the

You enter the midgame with a strange mix of air units, the ability to scout the map, and a surplus of minerals, usually around 1000. You should immediately throw down gateways, and an expansion.

If he's got mass hydra you're going to need carriers, so stop phoenix production, get a fleet beacon, and start making zealots.

If he somehow held you off with mass muta, you're going to want cannons in your mineral lines and more phoenixes before you can start making void rays again. You're going to want to try and kill him off before he can switch to hydras, as a hydra/corruptor/muta force will utterly destroy your air.

If he already has hydra/corruptor/muta you are going to need High Templar, so be careful here and get a robo for the observer and try to deny creep spread.

Take your phoenix and scout, make sure to keep an eye on his unit composition and stomp any expos ASAP. You might want to get speed prisms for this, I haven't tried it yet but I intend to.

Motherships don't seem to help much, and you really need the gas for everything else.

If you lose your army again it becomes Lategame.

If you planned on getting here you should have been getting upgrades earlier, and I mean all of them. You had a forge and a cyber core, so you could have been using them but why weren't you??? Did you really need that one more stalker?! The answer may have been yes, but, that's not going to get any sympathy. If you could get four bases do it, then you'll have enough gas... otherwise, you just won't have the upgrades to win.

Stick it out though. Because you may just have a Zerg out of the blue say "Holy ****, I just can't afford to fight you anymore" and GG. You may have mined out your main and be on one base and just sacrificed 20 zealots to kill all his drones but if you have been constantly killing his stuff you might just win.