Least Commonly used unit and why
 

Out of the dozens and dozens of characters in starcraft: brood war, I think that the Dark Archon is one of the least used units. I don't understand why this is so. They have the ability to cast maelstrom, which quite literally freezes the ravenous zerg dead in their tracks. The feedback ability is great too. Lets say you have a full energy Dark Archon (250 energy). YOu see someone coming into your base with five high templar. You feedback them for the mere cost of 50 energy. Your enemy loses one of the most vespene expensive units in the game. These two abilities alone should be enough to encourage their createion, but there is one more ability that these psionic entities posess. The brain-washing Mind Control ability. You can mind control a worker unit from another race, and beat your enemy in the face with their own type of units

If you were to ask me, there is no excuse not to get these units, so i can only guess why they are rarely produced. Im guessing that its because of the research required to unlock all of its abilities. That costs a lot of resources. Thats what i think, what d you guys think?

Well, I don't know about BW, since I only UMS on BW, but on SC the least commonly used unit is probably the ultralisk or the firebat.

Valkarye because people dont usually encounter super amounts of air.. that and devourerors for the same reasons but corsairs are only used because they dont bring down the protoss's protection by much in tvz so they can take out overlords

Hmm.. least used.. I haven't seen someone use a non-sieged siege tank in a while!

!! well it is common because in the beginning it is all you have to use against enemy dragoons for the first few minutes, you have to micromanage non sieged tanks if you dont wall.. non sieged is also common because zealot drops devastate sieged tanks so you have to unsiege before they drop onto your push uneless you have missle turrets.

You're right, you're right. The least used unit is definately the overlord. I haven't seen one in about two years.

vultures for terran, high temps for toss and scourge queens for zerg

AHAHAHAHA mydogisyourdog... ur a.... newb :( vultures is the most used terran unit !!!!!!! high templars are rarely used... scourges are used often enough and queens are .STARTING. to be used btu still rare.. but omfg.. what a money mapper :( heh play normal maps cuz money maps are gay/newbish and invading battle net

Not many people use vultures in original SC. I use queens regularly when I play zerg, they help out a ton.

dark archons are the shit!!!!!!!!!!!! i love useing them. i find hilariously ironic that ur killing people with their own forces. researching for them is a pain in the ass though.

P.S. Mc is the worst dark archon spell --a

i never ever see defilers or ultralisk when im playing a zerg

Another unit that i rarely seem to see is the infested terran. In fact....ive never had one used against me in a game. All the aformentioned units have. I guess people are just to lazy now a days to infest a command center. Youd think that the 500 dmg would be worth it. Tisk tisk.

Costs to much to use them, and it's too much trouble.

I use them but sometimes its just hard taking the damn CC from the Terran then defending it until it turns around and flies back to my base. But its worth it after. You guys have to see the destruction of doing a overlord infested drop on the Terrans! Its more pricey than a reaver but its still painful! Oh yeah, do remember to drop slowly, you dont want your infensties blowing the crap outta each other, big money loss then =(.

I would have to say the hyrdralisk. They pwn all.

Queen, Dark archon, Ghost.

What are you talking about? Almost every game i play against zerg, thney get hydralisks. They are such good units for there cost, so im gonna have to disagree with ya there zagggon.