My... Thoughts. (Green is for games, blue for buildings, yellow units. Purple is for abilities, and red is for upgrades.)
Heart of the Swarm
Zerg Spur Crawler
Role: Low Cost Early Defense
Requires: Hatchery
Built From: Drone
Abilities/Upgrades:
Bramble On
All buildings within range of the Spur Crawler gain an aura which damages attacking melee units.
The ability is channeled and ceases when the crawler is uprooted.
Once rooted again, the brambles and thorns take time to regrow onto nearby structures.
Uproot
Allows the Spur Crawler to unburrow andmove slowly, like the Spore and Spine Crawlers.
Uriticating Hairs
Attacking melee units will continue to take damage for 20 seconds after ceasing contact with structures.
Researched at Evolution Chamber.
Zerg Deep Warren
Role: Unlock Lurker Aspect
Requires: Lair
Built From: Roach Warren (Loses the ability to research Roach upgrades)
Abilities/Upgrades:
None (Researches the Lurker upgrade.)
Zerg Umbrate
Role: Fast Aerial Support Caster
Armament: None
Requires: Spire
Built From: Overlord (Loses all Overlord abilities)
Abilities/Upgrades:
Excrete Sludge
Covers the ground beneath the Umbrate in a thick, viscous creep that slows enemy units and
cannot be built or burrowed upon.
Channeled ability, does not cost energy.
(Works like Excrete Creep, has similar effect to Ensnare)
Amaurotic Venom
Blinds a targeted unit, reducing their visual radius to 1, and stopping detecting.
Permanent Status Effect.
Dark Swarm
Creates a temporary cloud that prevents ranged attacks from enemy units affecting all units within.
(Basically same as SC1, but also affects air units.)
Researched at Greater Spire.
Zerg Lurker
Role: Heavy Support Unit
Armament: Subterranean Spines
Requires: Deep Warren
Built From: Roach
Abilities/Upgrades:
Burrowed Attack
Seismic Spines
Grants the Lurker increased range, and the ability to attack up cliffs.
Researched at Deep Warren
Terran Control Tower
Role: Air Support Building
Requires: Factory
Built From: SCV
Abilities/Upgrades:
Tech tree change; All Air Weapons / Air Armor, and Raven upgrades moved here.
Tech tree change; Now required to construct Ravens.
Creates a similar radius as a Sensor Tower; Friendly air units within the radius receive a speed and vision buff.
Not cost effective to blanket entire map in them for effects.
Terran Field Technician
Role: Light Ground Spellcaster
Armament: None
Requires: Engineering Bay, Attached Tech Lab
Built From: Barracks
Abilities/Upgrades:
Ocular Relay
Enables the Field Technician to see, what its target sees.
Permanent Status Effect. (Works exactly like SC1 parasite)
Restore
(Same as SC1 Restore.)
Neurostim Blanket
Stops biological units within target radius from moving for a short period. They are still vulnerable to attack.
(Same as SC1 Maelstrom.)
Terran Scorpion
Role: Light Air to Air Fighter
Armament: Twin H.A.L.O. Rockets (Capable of attacking two units simultaneously)
Requires: Control Tower
Built From: Starport
Abilities/Upgrades:
Nanite Cloud
Covers a target area in a cloud of grey goo for a time. Units beneath this cloud cannot attack.
(Same as SC1 Disruption Web.)
Researched at Control Tower
Afterburners
Double the speed of the Scorpion at the cost of its ability to fire, and a much greater turning radius.
Scorpions who have had Afterburners activated for too long temporarily become non-responsive.
Transformation Ability (Think siege, or assault mode.)
Thermal Regulation
Increase the time window for Afterburners.
Researched at Control Tower
Further Terran Tech Tree Change:
The Viking is now built at the Factory in ground mode, and uses vehicle upgrades.
Protoss Argus Node
Role: Unlock Corvette
Requires: StarGate
Built From: Probe
Abilities/Upgrades:
None (Researches the Corvette Upgrades.)
Protoss Delphic Station
Role: Stationary Heavy Ground Caster
Requires: Cybernetics Core
Built From: Probe
Abilities/Upgrades:
Autonomous Power
Does not require a Pylon to warp in.
Sacrifice
Willfully send one of your own units back to the Void, granting the Delphic Station additional energy.
Shield Battery
Recharge friendly shields in exchange for energy.
Gamma Ray Burst
Irradiate an enemy biological unit, causing it damage, and damage to other biological unit near it.
(Same as Irradiate from SC1.)
Gamma Ray Field
(Same as SC1 plague.)
Researched at Cybernetics Core
Tidal Flux
Raise the very Earth around the Delphic Station, creating cliffs that impede vision and provide a choke.
(Permanent; Only usable once per station.)
Researched at Cybernetics Core
Protoss Corvette
Role: Slow and Heavy Air to Air Fighter
Armament: Neutron Crystals
Requires: Argus Node
Built From: StarGate
Abilities/Upgrades:
Overload
For 10 seconds, the Corvette is immobilized, and given 8 attacks per cool down cycle, rather than one.
After, requires 10 second cooldown before it can move or attack again.
Researched at Argus Node
Plasma Charge
A melee range attack with high cooldown that can only target one building at a time, deals 800 damage.
Researched at Argus Node
Tractor Beam
For: Phoenix
Researched at: Argus Node
Ability:
Channeled ability like Graviton Beam, but draws enemy air units closer. Units affected can still attack.
Useful for drawing in fleeing units to slow crowd of Corvettes. Does not affect Motherships or Colossus.
Void Reap
For: Dark Templar
Researched at: Dark Shrine
Ability:
Instantly kill a ground enemy unit at the cost of revealing the Dark Templar for 10 seconds.
Dark Haste
For: Dark Templar
Researched at: Dark Shrine
Ability:
Increases the Dark Templar's walking speed.
None.