I'm in the process of putting together an SCII project (not sure if it's going to be a single, lengthy scenario or an entire campaign) that will explore some of the 'starter' evolutions that the Zerus Zerg had, prior to the advent of the hivemind concept discussed in the later pages of this thread.
Of course, I have no idea whether or not the discussion is revolving around actual facts or it's a bunch of derps grasping at straws, but either way, the concept was interesting enough and I've been mulling over some ideas.
I've re-done the entire Zerg techtree, and changed a lot of how the mechanics of how the Zerg play. They no longer mirror any other race in terms of resource gathering, nor do they mirror the Zerg's own mannerisms when it comes to unit production. This thread is not meant to assess how well-balanced or playable this new iteration of Zerg would be, but to debate whether or not the evolutions and strains I've done up are feasible - in that, they aren't too powerful, and where the Swarm is now, it's clear what ended up superseding the past evolutions.
As a side note, I've tried to make contact with GnaRefotsirk for his modelling talents, but if anyone else is (or knows of) a good modeller, feel free to contribute. I have visual concepts in mind for many of these, if not all of them.
Below is a list of the entire re-done techtree. As of the time of writing, evolutions (researches/upgrades) have not been designed - only units and structures.
Now I will take each individual piece of the above and explain it in full, point to the new, better evolution we see in today's Zerg, and give my reasoning for why the new one is, in fact, better than the old one.
The Gestator is a structure that envelops mineral fields and literally siphons the resources, using specially-adapted material. The resources are then converted to a viable 'energy' by the Gestator, and are then stored within the reserves of the creep. Gestators themselves spread creep, and are one of two ways the Zerg has in order to facilitate creep spread. These structures also serve as builders, able to construct every structure in the Zerg techtree, so long as there is creep available. Gestators were superseded by the far-more-efficient Drones, who were able to gather minerals and morph into structures much faster.
Caveat - These cannot grow over Vespene Geysers. I'm uncertain if Vespene will have been integrated as a viable resource for the Zerg at this point. If not, there will be no need for Geysers, but I will still place them in odd spots around the map(s) to show that Zerus does have such things.
Possibility - Instead of having the Gestators store the mineral essence in the creep, they might store it within themselves - which would mean that players would have to spend the resources in order to free up space in the Gestator's own reserves. I don't think that makes as much sense, but it could be an interesting gameplay mechanic.
The Stalks serve as nesting grounds for Overlords, who in turn act as early sentries for the Zerg. Supply (called 'Nourishment' for the Zerg) is generated by Stalks as they energise the creep. This not only provides nourishment for the Zerg armies, but also keeps their structures intact - they passively feed off the creep in order to stay alive. While Gestators can supply enough Nourishment to support a cluster's structures, Stalks are needed in order to morph the larvae into units. Overlords eventually surpassed the Stalks when the hivemind took effect and the creep evolved into a self-nourishing substance.
Zerg Greater Stalk
Greater Stalks are one of the several structures which provide the Zerg with larvae. Despite what the name may imply, Greater Stalks are not gestated from the smaller, more basic Stalk, and do not serve a similar purpose. Greater Stalks instead serve as a basic combatant producer, unlocking new combat options and providing the player with the first Zerg military unit. The larvae of the Greater Stalk are morphed within the structure's thick carapace, and are as such invisible to the player (and cannot be destroyed by enemies). While the extra protection was insurmountably important during the Zerg's early days, the larvae were often deprived of nourishment from the creep, causing the morph times of units to be undesirably slow. When the larvae eventually evolved a thick exoskeleton, rendering them almost impervious to most attacks, the course of evolution took its place.
Caveat - There is no 'Hatchery' type in this iteration of the Zerg. Greater Stalks currently train a single unit, and many other structures higher up the tech tree train more powerful combatants. The Greater Stalk feels more like a Barracks or Gateway than it does a Hatchery; the only reason to keep them, aside from allowing the construction of much-needed Caverns, is so that you can continue to spread the creep with Creeplings. A possible solution to this is moving the Swarm Collector from the Cavern to the Greater Stalk.
The Zerg are not the only thing I'm fanconning - Zerus is also included. While it is known that the planet is, in essence, a volcanic wasteland, the Zerg evolved there, with the guide of the Xel'naga. In this setting, Zerus is a catacombed planet with massive tunnel systems. The Zerg used these tunnels and catacombs to traverse across the battlefield very quickly. Caverns function much like Nydus Networks do, but can not spawn exits - additional Caverns have to be gestated, limiting their use. Another limitation is that such a system of transport would be borderline unusable anywhere else, as it requires a system of caves to be present on the planet. This eventually lead to the evolution of the Nydus Canals, Networks, and Worms, replacing the Cavern as a quick method of transportation. Other than serving as transport systems, Caverns can produce resilient combat units; the structure captures creatures of the deep and gestates them unto a Zerg creature.
Possibility - Instead of having Caverns built on creep, perhaps they should be gestated over entrances to the bowels of Zerus. This would especially make sense, gameplay-wise, if Vespene was not included, because I could place these cavern 'openings' near viable base sites (and in strategic areas).
The Olakraat is a structure that combat-specific evolutions take place in. Rather than having a set of incremental upgrades, every unit will have at least two evolutions to improve its combat efficiency, and will additionally have 'tradeoff' evolutions - research one or the other, depending on what the situation at hand calls for. As an example (note that this may or may not be in the final product), say you have a tradeoff evolution for the Creepling. One improves its speed, the other improves its armour. Once you choose one, you cannot evolve the other, unless you restart the mission or move on to the next mission. The Olakraat facilitates many of these tradeoff evolutions, and unlocks many basic upgrades (an example of a basic upgrade for the current Zerg Swarm would be the speed upgrade of a Zergling, or the range upgrade for the Hydralisk). Note that the current evolution system doesn't have any incremental upgrades, such as 'Melee Attacks' or 'Air Carapace'.
Zerg Fungal Den
The Fungal Den is the first (and only) Zerg structure from which players may morph air units. It is also the source for the most advanced evolutions for most military units, essentially acting as tier 2 and tier 2.5 technologies. The Fungal Den also enables an evolution for the Cavern that allows the genetic rewriting of more powerful creatures, enabling the morphing of an additional unit. The Fungal Den was replaced by the Evolution Chamber when less specialised, more general evolution strains were discovered.
Zerg Carrion Lair
The most powerful units in the Zerus Brood's arsenal are morphed and gestated at the Carrion Lair. These are the tier 3 units, and as such are enormously powerful, incredibly useful, and especially costly. The Carrion Lair doesn't unlock any new evolutions for lower-tier units, as that purpose was largely served by the Fungal Den. The Swarm's more powerful units have since been superseded by the Defiler, the Infestor, and the Ultralisk, but for their time, the Swarm Lords and Swarm Aberrations were the dominant Zerg creatures on Zerus. As the units it morphed and gestated faded into obscurity, however, so too did the Carrion Lair.
Zerg Aberration Chamber
Essentially an Olakraat/Evolution Chamber for tier 3 units, the Aberration Chamber provides many evolutions for the Swarm Lord and the Swarmling, as well as many tradeoff evolutions that mostly effect the Swarm Aberration. The Aberration Chamber can even upgrade some of the Swarm's structures; its services were soon outdated, however, as the Swarm's units and structures evolved.
Zerg Impaler Colony
Not much changed between the Impaler and Sunken Colonies. While its predecessor had a slightly more obvious attack, the Sunken Colony itself has tougher carapace and a more powerful tentacle strike. For its time, though, the Impale Colony served as an invaluable base defence.
Caveat - You may note that there is no anti-air defence. This is not an oversight, but merely a more obvious sign of evolution.
Zerg Creep Spore
An early iteration of the Creep Tumor, Creep Spores are implanted into the earth in order to spread the creep. While just as frail as the Tumor, the Spore is not hidden from plain sight, and as such is very vulnerable. Creep Spores are necessary to create Gestators; without them near a mineral field, you cannot morph the absorbing structure. Creep Colonies would first surpass these weak structures, as they were tougher and could eventually morph to defend themselves.
This large, slow-moving airborne creature should be familiar to everyone. It comes without the benefit of supplying control, but instead have the ability to detect hidden enemies and attack airborne units with a powerful bite attack. They were re-evolved as overseers of the Swarm when the hivemind aspect of the Zerg became fully-fledged.
Morphed at the Stalk.
These small Zerg were perhaps the first iteration of the iconic Zergling, and exhibited many similar traits - frail alone, but devastating in numbers. The Creepling also served as the most prominent method of spreading creep, able to implant small spores into the edges of Zerg territory in order aid the Swarm's expansion over Zerus. The implanting of Creep Spores, however necessary, results in the death of the Creepling. As such, players will have to be on their toes early-game, and careful of how they handle creep spread and base defence.
Morphed at the Greater Stalk.
Zerg Swarm Collector
Though the Roach may not have evolved until after the Great War, the Swarm Collector bears a resemblance in combat role, if not in appearance. While this unit isn't as tough or powerful, it's the first ranged combatant that the player can procure, and it's best used as ranged fire support rather than as the backbone of one's army.
Morphed at the Cavern.
Zerg Swarm Hound
The Swarm Hound is a ferocious melee combatant that is significantly more powerful than the Creepling, but not as sturdy as a modern-day Ultralisk, by any means. These creatures are very agile, bearing somewhat of a comparison to feline critters of Earth or even the jungle cats of Aiur. When the Zergling replaced the Creepling as a the prominent melee attacker of the Zerg, the Swarm Hound was no longer necessary to add to the sheer force of Zerg armies.
Morphed at the Cavern.
Small but quick, Zerg Euterion are swarming air creatures that spit acid at other airborne units. Though two spawn from every egg, they are still incredibly frail, and should only be used in swarms - hence the adjective, 'swarming'. They were replaced first by the Scourge and then again by more powerful anti-air units like the Devourer and the Corruptor.
Morphed at the Fungal Den.
Zerg Swarm Talon
The Swarm Talon is a medium-sized airborne creature, notably faster than most other Zerg. In small swarms, these units are ideal for hit-and-run tasks, kiting enemy units, and overwhelming enemy positions. Swarm Talons are decent at aiding main armies, though are most commonly found acting as air support or surgical strike forces. The Mutalisk eventually superseded the Swarm Talon, proving its superiority in both agility and attack power.
Morphed at the Fungal Den.
Swarmlings are small, fast, and frail creatures, more powerful and agile than Creeplings as combatants. Two Swarmlings are gestated with each morph, but a vast number is necessary to overwhelm the enemy, even so. It is also worth noting that these creatures cannot produce Creep Spores, so Creeplings are still necessary to spread the creep. Swarmlings were eventually replaced with the slightly-stronger Broodlings, but even those have rarely made it onto the battlefield.
Morphed at the Carrion Lair.
Zerg Swarm Lord
The Swarm Lord is the essential spellcaster and powerful army breaker rolled into one. It has abilities extremely viable to the progression of the Swarm's armies, as well as a powerful ranged attack that makes it extremely dangerous. The Swarm Lord's abilities were eventually outdated, but the need for a spellcaster and a powerful unit did inevitably arise - giving birth to the Defiler, the Infestor, and the Ultralisk.
Morphed at the Carrion Lair.
Zerg Swarm Aberration
The Swarm Aberration is a melee variant of the Swarm Lord, able to cast spells and modify its stats based on what tradeoff evolutions the player evolves at the Aberration Chamber. Essentially a more customisable Swarm Lord, the player will find that these can easily be the most powerful units in the Swarm's arsenal.
Possibility - Limit the amount of Swarm Aberrations the player can construct to two or three. This will make the units that much more valuable, but prevent the player from artificially attaining critical mass.
Morphed at the Carrion Lair.
This evolution is specific to the Gestator that is upgraded. It improves the absorption material that the Gestators have evolved, improving the rate minerals are harvested.
More to come. Share your thoughts on what you think of it all.