Defiler Ability: Acid Rain

dark swarm is best used against static defences (buildings)

 

But...
If they're Zerg, they can cast another Dark Swarm, with their Defiler, on their Colonies, protecting them from you.
If they're Terran, they can drive a lot of units out of there with Irradiate, from their Science Vessel, because all of your units are clumped in a small area so it's doing damage to all of them, and because you can't see which unit is affected because the Dark Swarm is covering them.
If they're Protoss they can cast Disruption Web, from their Corsair, into the Dark Swarm preventing your guys in it from attacking out of it.

 

Dark Swarm doesn't protect buildings. Al of the counters you note also have to be researched, if the enemy does not have prepared Science Vessels, Corsairs, etc, they won't be able to deal with the ability.

Also, when I get Defilers, Consume is the first thing I research. The biggest advantage of the unit is the fact that, with a little cheap fuel (Zerglings) you can unleash all kinds of pain onto your enemy.

 

My Defiler just always seems to just be left burrowed and forgotten somewhere on the map, and I only end up using it when I'm in the mood for a bit of a novelty. I never come across a situation where I think, 'Boy, I could really use a Defiler about now!".
But when choosing between Defilers to Queens, it's a no-brainer for me. Most likely it's just my style of play, but I seriously never feel I need a Defiler to improve my army. With multiple Queens (3 - 4), I'm able to do frequent Broodling runs sending one, sometimes two, at a time, but not sending all at once. On the run the Queen has enough energy to cast Spawn Broodling as well as Parasite. Often, because the opponent is focusing on the unit that's been Broodling'd or on hunting down the Queens, which they can't reach if your other queen is able to Ensnare them, that they don't immediately notice the Parasited unit which allows you a small amount of time to gauge their forces or scout their base. I'll always have at least one Queen back at the main base on just about full energy in case of emergencies.
But with Defilers, they might be able to do Plague runs, and use Dark Swarm for their retreat, they do not actually completely kill any enemies, and all the teams have some way of regenerating that lost health, regeneration on Creep for Zerg, Medics/SCV's for Terran, Shield Batteries for Protoss. But I do realise how devastating an effect Plague can have on buildings. However what I look for in a caster, is something with good survivability, that can harass the opponent, and do quick in-and-out raids between my army's main assaults, which is why the Science Vessel is also one of my favorite spell-casters in the game!

 

i have never been much of a Queen user when playing with the Zerg.sure,they are useful,but i never really used them a lot(i seldom use them,actually),i think the Defiler is a bit more useful than the Queen.sure,spawn broodling is fun and all,but Dark Swarm,Plague and Consume make the Defiler much more deadly(not really,since plague doesn't kill,but you got my point),and an excellent support caster.having them using plague ont the enemy army or static defenses make your loss diminish by a quite a bit,dark swarm (more like orange swarm to me ^^) is a good protection spell,and consume gives the defiler good mana.i would be happy just with the defiler being able to kill things,if they make a come back,that is...

 

Congratulations, Itzahexgor, you have been successful in swaying a bit of my opinion about the Queen.

Note that I didn't say that you've swayed my entire opinion, because I still feel its abilities are a bit weak compared to other casters, and that it's too expensive in both mineral/gas and energy costs for what it does.

However, its mobility is definitely a plus, as well as the fact that it's a rather sturdy unit. The Defiler is slow, and weak.

 

parasiting science vessels works great, they are too expensive to be sacrificed giving you a free scout.

 

Science Vessels can still be Restorated by the medics, can't they? I feel that the best units to Parasite are workers, because they show the layout your opponent's base, or not-too-powerful-on-their-own-yet-still-expensive units, like Siege Tanks, Archons, and Guardians/Devourers, so that the player will not want to sacrifice the unit but it can't do any irreparable damage if they send it in. Often if players have one of their Carriers/Ultralisks/Battlecruisers Parasited, then they will send all of them for your main base. This can be annoying if you just wanted to keep tabs on the Carriers/Ultras/BC's to see when they're about to attack because your not prepared for them yet. Also, if you cast Parasite on one of their weak units, Zealot/Marine/Zergling, then they'll either kill it themselves or send it on a one-man charge. If a Science Vessel/Queen/Arbiter, is parasited they are usually just kept away from the base, so they don't give away any information, but can still keep doing their job (although less effectively).

 

few people bother to research restoration for the medics, and sv is the biggest headache for zergs against terran. they keep diving forward to irradiate your lurkers and defilers, with parasite, you can see them from miles away

 

True. Never thought of that counter. I'm going to have to use it on Ych9, he is terribly annoying with those SVs of his.

 

But is you have Medics, and if your playing as Terran you will, and see that a lot of your units, or an important unit is Parasited then it is all to simple to just keep your Science Vessel from revealing too much information of your base, while you research Restoration. Then, once you've got it, you can always cleanse any Parasite off any of your units. When using Parasite you should not be looking for a long term scout, you should try and get something that they won't realize has been Parasited for a while, and allows you to get a quick analysis of their base or army.