However, I thought about the ranged backbone units of an army. Ranged tanking units which also do alot of damage in a matter that did not exist in Broodwar.
Tanking Ranged Units
Marauders
Marauders seemingly developed from the Firebat.
However, they have a very different job. I do not know if Blizzard ever believed in their words when they said it was a supporting unit. Supporting Units cannot be expected to be reduced to a supporting role when they are cost efficient against a group of units as big as "everything that runs, crawl or glides around on the floor and does not fly". Also, seemingly their design was mixed with that of the vulture, resulting in a grenade throwing infantry and a flamethrower harassment unit.
Roach
Why do they exist? I always wondered why. Zerg had Zerglings, Mutalisks, Hydralisks, Lurker, Defiler, Ultralisks to fight with. A small number compared to Terran and Protoss, maybe Blizzard thought it was too small?
I remember Blizzard how they presented the Roach as a new harassing unit. This makes few sense to me. Not only when I look at what became to roaches, but also because Zerg had Zerglings which are the essence of annoying, cheap, quick harassment everywhere on the map in every stage of the game. Possibly they wanted to redesign the way Zerg would harass into a more micro intensive way since Roaches were made for harass, then run, burrow and regenerate. However, why would they want to reduce the importance of Zerglings and possibly Mutalisks?
Roach and Marauder really are dumb and boring units. They live, they a-click, they are cost efficient and nothing else will ever happen to them.
Sentry
First it was the “Star Relic”, a flying support unit with hallucination and an area cloak for allied units. Then it became the “Stasis Orb”, lost it’s ability to fly and should support by slowing down opponents, then the Nullifier and now it is a Sentry. For me, the Sentry is what Roach and Marauders are although it is so different. Protoss already had their early tier cost efficient ranged nearly allround almost tanking unit. What lacked of Terran and Zerg, a simple and always strong early tier unit, they had it. Protoss depended on all those Gateway units. However, with the Sentry as an addition, it became even stronger. That’s why I equal the addition of Sentries with those of Roaches and Marauders.
Effect of these Units
Combat
These units take a lot of the non-straight-ahead army compositions of Broodwar. What I mean is that Broodwar armies are mostly not good in simply beeing send into combat with a-click. Many army compositions are not just there and ready to deal damage and receive it. Tanks need Siegemode, Vultures have to place their mines or strike where there is too few resistance. Zerg armies need positioning, possibly Lurkers to be burrowed or Dark Swarm to be used at the right locations with the right timing. Protoss, as I said, already had their simple backbone units, Zealot and Dragoon, so maybe combats did not change so much for them. However, they had to respond to all these things Terrans and Zergs did.
Other than most Broodwar armies, SC2 armies have way more simple always-ready-Units that just move in and fight and are cost efficient. Instead of Dark Swarm or Lurkers or flanking with Zerglings, Zergs mostly have lots of Roaches and Hydras which just move forward and attack. Terrans often have their marauders which do not need all the position play that Tanks or Spider Mines made necessary. They do the simple a-move and fight style that was almost impossible for Terran to do in BW. Protoss possibly had the lowest impact by changes made to them for their own style, what rather changed are their relations to other races.
In german there is the expression of “Um die Ecke denken” (to think around a corner) which basically says if there is no direct way to achieve something, do it indirectly (I do not know if there is a similar verbal image in english). For me, this indirect style was typical for Broodwar. There always was one corner before just doing something. You cannot send a mech army or almost any zerg composition into combat just by doing a-click. There was positioning and other things before that. A Lurker cannot even attack directly, it has to burrow first. These are no things necessary to most SC2 armies. OK, do not move your vikings in front when facing colossi. Use stimpak. But still, the basic experience is a-click and go. Even the experience of playing Siege Tanks is different since it’s not possible to use armies as heavy on siege tanks as there were in many TvT/P in BW, rather they always have to stay behind a bio ball and occur in numbers of 6 or less (Ok, that’s not true in TvT actually. But honestly, TvT is strange with this extreme air heaviness. It almost doesn’t count as a full-value matchup to me).
I believe that it also affected Ling/Utralisk indirectly. The new focus on almost always smaller games and straight a-click cost efficient ranged units would make Dark Swarm unbearable so it was removed and left Crackling/Ultralisk in a position where they could not fight at all.
Strategy
This massive increasement of tier one cost efficiency compared to higher Tiers not only makes battles more simple, it also changes the face of the whole game. Greedy Build Orders do not even have to be very greedy compared to Broodwar, but already they get easily demolished by the simple cost efficient low Tier units. The responding player does not have to take a risk like beeing in a economic disadvantage, because the response with cost efficient low tier units is due to their a-click cost efficiency almost a certain victory over less expansive forces. Since expanding or fast teching players naturally have less money to invest into forces before the expansion pays off or the higher tier units are available, they are forced to use their units in an extra cost efficient manner just in order to survive or delay their opponent until the disadvantage is gone.
Possibilities are, for example, Bunkers, Sunken Colonies or Photon Cannons which are, as they are immobile, cost efficient defense, or pretending to be aggressive while hiding the expansion. Or threatining the opponent’s base with quick units so a big push would endager him to loose all of his economy as well.
The appearance of early game stage a-click cost efficient units makes these tactics futile. Using the same units would mean to have less. Since there is few possibility to use other factors like terrain to an advantage this big in early game stages, it would lead to a loss. This is clearly visible in attempts of Marauder-Fast expand versus Protoss which got crushed the moment marauders were not be great at super early game aggression when Concussive Shell became an upgrade. No early aggression, simple numbers-against-numbers fight, Terran had less because he invested into an expansion, Protoss won. The units which lead to this success were Sentry and Immortal, both making Gateway compositions super efficient. Immortal is just another early available combat unit that is strong in straight combat, not comparable to Reavers. Also, they have Voidray, a bit more harassing focussed but still a strong front buster, and early available.
Same against Zerg. Early, Zerglings are too few to win against Marines in a Bunker. Building more would mean to go almost or fully all in because it would cut the worker count too drastically. Later, the expansion already paid off and Zerglings would just melt to Marines once there are enough. Instead, they even have two units allowing early aggression, which are Roach and Baneling. Banelings demolish the attempt of defending cost efficiently with marines and bunkers, Roaches threaten the Terran to use Marauders, Marauders means no defense to Mutalisk, early expansion idea is dead.
Since it is so uncomplicated to bust early expansions of Protoss or Terrans, there is almost no chance of greedy games in which expansions get countered by even more expansions. Rather most games develop around full scale pressure.
Some changes made to other Units/Game Design
High Ground Advantage
The change to high ground puts even more emphasis on the low tier cost efficient units! Given that there is noticable defense on a high ground, just do the push when there is something to get vision. Such as an Overlord, an Observer, or Vikings/Medivac/a Scan. Then there is no advantage at all.
Vulture -> Hellion
Possibly, this was made because Blizzard does not like long lasting games with delaying strategies. I think spider mines are the one perfect example of how one skill can lead to massive delay and slow positioning games. As far as I remember, they wanted the game to be faster, so no surprise they removed it. Other than that, I cannot believe what they did. The Hellion just became 10% as difficult to control and 5% as possibly effective as a Vulture. Why did this have to happen? They mixed Firebat and Vulture to the worst possible outcome. Even I, though few personal BW experience especially compared to the community on this page, know how cruel micro became once vultures occurred. And sim cities to keep them out of eco lines where they would have a happy time. They had an impressive collection of tools to fulfill their duties. They could give a great advantage in combat/positioning, gain map overview and controll, harass and counter melee units. To do this, they had a strong attack against light units, especially when compared to their costs, great speed and control with hold, attack and patrol, or short, a moving shot when controlled well, and spider mines. They could delay the opponent in his army movement, force him use more than just one or two heavy units to drive them off or gave precious extra time for harassment and gain map overview. Hellions just cannot do any of these things. What it can is harassing an opponent while he does not have units to defend at all. It cannot even use moving shot to win over purely light melee armies. Actually, an SCV armed with a water gun could do the same.
Wraith/Goliath -> Banshee/Viking/Thor
Just to confirm Lalush’s “terrible terrible damage hypothesis”, replaced controll of Wraiths with damage and less versatility. Potential effectiviness of all air units shifted towards the “Tactical” corner while loosing lot of Micro as a factor. Tactical actually means it only depends on what is on the field compared to how units on the field are used. Vikings were possibly once thought as bringing more micro in? Too bad they are too expansive and slow for doing any harassment.
Science Vessel -> Raven
I think that Blizzard hates the event that very very very often occurred in Broodwar: Absolute lack of power against loosing units.
1. No Moving Shot on Vultures, I guess any player knows this feeling of only beeing able to watch how a couple vultures eats a gigantic mass of melee units?
2. Radiation gone. It’s the even better example. Just gone. Instead, Raven has HSM which is very reactable.
Also, it looses EMP to Ghosts, maybe Blizzard noticed that they overbuffed Protoss gateway and had to give an early counter to it.
Voidray (Scout?)
Ok, it requires micro. However, it is another direct-to-use unit.
Scourges -> […]
Gone, a big loss for micro. Dunno why they had to go, possibly they just went because the graphics guys once thought it looks silly when Air units have few acceleration and Scourges just killed them when they had too much of it.
Arbiter -> Mothership
RECALL RECALL RECALL! Not anymore, or could you imagine that someone would not notice a flying saucer as big as a soccer stadium and as slow as your grandmother floating into his base in time? A huge loss for late game since stasis is more or less a skill that will be used for one time in a game, given that a mothership will appear at all.
High Templar
Now it is the I-counter-everything-Unit that counters everything by either storming or feedbacking them, or both. It gives even more importancy to Marauder/Roach since both of them have enough HP to live through storms, more or less.
To come back to the initially mentioned units and overall topic:
I do not see why Blizzard might want to introduce such boring Units as Marauder, Roach, Immortal or bring in an early game casting unit like Sentry to buff T1 armies. I think they ruin the game to a certain degree.
The only reason I could even imagine why they wanted to make them is that they want to force a difference to broodwar.