Like they keep up constant harass then get a gigantic ball of archons and blink stalkers.
Its probably much easier if they never harass, but been constantly harassing.
All they do is blink the stalkers back so the archons are in front and they deal 30+ damage to all zerg units, and has splash. And thats not even including the stalker support from the back. Speedlings doesnt work to take out the stalkers cause archons melts them in a couple of seconds.
Sometimes they have a few sentries for guardian shield.
Maybe mass roach/hydra and let the roaches tank for the hyrdas and the archons cant get to the hydras? But then what about the blink stalkers?
Is it just archon/stalker? No air support?
Tech units are your friends here. You absolutely under no circumstances want to throw your army into this one in a slugfest. They will crush anything and everything you throw at them if theyre able to fight back fully. Fair fights are the protoss’ strength and the zerg’s weakness, so avoid them at all costs.
So brood lords, vipers and infestors are what you want to look at here. You want to keep the archons at bay as best you can. Fight in chokes, fungal them, abduct them to pick them off, your goal here is to only ever engage the very edge of the ball. Brood lords have enough range that they can attack the archons without immediately being shot back, but the stalkers will want to blink under them, and archons move faster than brood lords, so its important to pick youe engagements carefully so the protoss player cant control the terms of the fight.
Archons are fat, so they really suffer in narrow spaces. If you fight at a ramp and get a good fungal off while theyre trying to go up, you can get some good delays on them to just unload with the brood lords. If the protoss is dumb and/or aggressive, they might send the stalkers ahead of the archons, but if you can keep the archons back, the brood lords can probably take just stalkers in a straight fight, especially if you hit them with your spellcasters.
They are always in front of the army not because they deal that much damage, but because of 350 shields and huge size, which makes them great to absorb the banelings damage, which otherwise would be a total disaster for stalkers.
Archons have small attack and splash range, so they are good against muta, which also has a small attack range, they are not good against long range units such as lurkers, against roach-ravager, because when the units have a huge model, archons splash doesn’t work that well. Archons are good against lings, because the size of lings is really small, same as the distance between them, so archon can damage many lings at the same time.
As you said – roach, hydra, lurkers are the units you would use to kill a t3 300 gas unit.
The BL ‘ammo’ will cause a lot of problems for Archon movement all by themselves, and can make this into a real micro battle, agree that FG will help a lot. A couple of lurkers burrowing just behind the BL ball can help weaken/pick off those who struggle ahead, especially some stalkers.
Have a few mutas around as a ‘screen’ for an overlord to spot observers when they show to see your lurkers.
hydra lurker with an arc. stop F2ing - archons arent the problem, immortals and high templar will screw you over, just avoid getting stormed or avoid fighting immortals when they arc, they WILL win
Roach ravager, mix in some lings to tank the splash/stalkers, queens are also good on defense. Kite back with your ravagers and make concaves, if it goes late enough fungal counters blink and neural archons. Add banes if he adds chargelots.