Video Game / StarCraft II: Co-op Mode

StarCraft II: Co-op Mode, also known as Co-op Missions, or Allied Commanders during the earlier stages of its existence, is a game mode in StarCraft II, released with the third expansion StarCraft II: Legacy of the Void.

Co-op Mode is a two-player game mode where each player plays as a character from the StarCraft universe. Players are dropped into a map with just their starting base and six workers like a melee map, but their tech tree and tactical options are vastly different, reflecting the personality and story actions of their character — for instance, Jim Raynor commands massive infantry armies and can call in the Hyperion battlecruiser to fight for a short time. Each map has different objectives, variably demanding players to take out key enemy buildings, defend objective points from enemies, or secure important areas for a period of time. Many missions are repurposed from the single-player campaigns, but some are unique to Co-op.

Co-op Missions was originally simply intended as a way to give players who were interested in the single-player campaigns and the story lore a way to keep playing Starcraft II and enjoy it with other players, without having to transition to melee play (which is much more competitive and plays very different from the single-player mode). However, the mode became unexpectedly popular among the playerbase as a whole; according to a developer in November 2019, it was the most widely played game mode of StarCraft II at that time. Thus the mode saw continuous support with new commanders and new missions, balance updates, and new gameplay features. This includes the addition of weekly "mutators", missions where the maps are given new quirks, like temporal fields that slow time randomly appearing, or enemies that grow stronger as their allies die; and "Masteries" and "Prestiges", which let the player further power up an aspect of their character's playstyle in exchange for another aspect being weakened — for example, Artanis can make the active abilities of his units stronger, but the units themselves are more expensive.

The base commanders — Raynor, Kerrigan, and Artanis — are free to all players, while other commands must be purchased or come bundled with other StarCraft II items, depending on which commander and the time in question. Players can still use the paid commanders but their level caps at five, limiting how effective they can be until purchased.

Playable commanders include:

• Terran: Jim Raynor, Rory Swann, Nova Terra, Mira Han and Matt Horner^note The two are treated as one commander, Tychus Findlay, Arcturus Mengsk.
• Zerg: Kerrigan, Zagara, Abathur, Alexei Stukov^note Stukov combines elements of Terran and Zerg gameplay, but he is primarily considered a Zerg commander, Dehaka, Egon Stetmann^note Stetmann is a Terran but his army is a "Mecha Swarm" of robotic Zerg
• Protoss: Artanis, Vorazun, Karax, Alarak, Fenix, Zeratul

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Tropes found in Co-op Mode include:

• Absurdly High Level Cap: The initial level cap was indeed high (90 Mastery levels, on top of the 15 needed for any given commander), but nowhere near ridiculous. Then Patch 3.17 dropped, bumping the level cap up to 1,000, so players at maximum Mastery will have another 910 Ascension levels to go.
  • Patch 5.0 introduced Prestiges, which add a further 45 levels to each commander. If you're looking to fully max-out your co-op profile, that's 2,080 levels in all, Mastery and Ascension included, so get busy.
• Acceptable Breaks from Reality:
  • The enemies in "Malwarfare" are Hard Light holograms, but they still drop biomass for Abathur and essence for Dehaka to prevent these commanders from being denied their core mechanics.
  • Provided it's in their AI script, Amon's forces are capable of using all units of all three races, not just the ones his forces had in the Legacy of the Void campaign, including not just units based on Purifier technology that were created by Karax during the campaign, but also Nerazim units like Dark Templar and Void Rays, when it was a major plot point that Amon couldn't control the Nerazim. But if the AI was limited to just the unit compositions featured in the campaign, they would have limited options and gameplay would quickly get stale.^note Given that "Chain of Ascension" revealed some of the Tal'darim stayed loyal to Amon after Alarak became Highlord, you could Hand Wave that they're among his forces as Dark Templar, Void Rays, etc., and stole the Purifier technology for him.
• All Your Base Are Belong to Us: Quite literally with the "Eminent Domain" mutation. Should the enemy destroy any of your structures, they will be restored to full health and converted to Amon's control. If a building is garrisoned with troops when it is destroyed, all personnel inside will be lost, and Swann players will lose their Drakken drill permanently if it's captured, since it will just keep rebuilding itself even if you destroy it, but as an enemy structure with no way of getting it back.
  • That being said, this can also work in the player's favor on some maps, especially "Dead of Night", by erecting a wall of disposable structures at the barricades specifically to be converted. While the AI will destroy structures normally if it cannot path a way into your mineral line, Terran buildings that burned down on their own will also count as having been converted and will be "safe", as they will not attack one of their own and therefore cannot advance into your base through a given route, making this a potential A.I. Breaker in some cases.
• All Your Powers Combined: Some units in Co-op Mode are fusions of units variants from the game (campaign and multiplayer). The biggest and most notable examples are:
  • For Vorazun: her Dark Templars have Blink (from the multiplayer version called Shadow Stride), Shadow Fury (from the Nerazim Dark Templar), Void Stasis (from the Tal'darim Blood Hunter) and a Talent gives Emergency Recall to all cloaked units (similar to the Aiur Avenger), and with the right prestige, it also fully heals them just like the Avenger. It is essentially a fusion between all variants of the Dark Templars in StarCraft II.
  • For Kerrigan: like Vorazun's Dark Templars above, Kerrigan's Hydralisk is a fusion of all variants of the Hydralisk in StarCraft II. It has the Muscular Augments upgrade (which both increases its movement speed and its attack range, combining the multiplayer upgrade of the same name with the Grooved Spines upgrade from the multiplayer/campaign), the Ancillary Carapace (which gives them +20 maximum hitpoints) and Frenzy ability (which boost its attack speed by 50% for a short time), and Kerrigan's Hydralisks can have all of those upgrades at the same time. For comparison, in the campaign, the Hydralisk lacks a speed upgrade and it can only have one of those three upgrades (Grooved Spines, Ancillary Carapace and Frenzy) per mission (but they are interchangeable between missions). In the same vein, her Ultralisks can be upgraded with Chitinous Plating (their multiplayer armor upgrade) as well as both Burrow Charge (exactly what it sounds like) and Tissue Assimilation (gives the Ultralisk Life Drain), the latter two of which were mutually exclusive in the campaign.
  • For Zagara: her Banelings can be upgraded with both Corrosive Acid (double damage to primary target) and Rupture (bigger explosion radius). Like the Hydralisk example above, those upgrades cannot be selected at the same time in the campaign (also interchangeable between missions).
  • For Kerrigan and Zagara: Their Zerglings get to use all three of their campaign upgrades at the same time, giving them bonus health, attack speed, and movement speed (plus a Co-op exclusive upgrade that causes them to nullify the armor of anything they attack).
  • For Abathur: His Roaches have Tunnelling Claws, Adaptive Plating, and Hydriodic Bile, their interchangeable upgrades from the campaign, and they also have the Glial Reconstitution upgrade from melee.
  • For Karax: His Immortals have the Barrier Ability from the Aiur Immortal and the Shadow Cannon from the Nerazim Annihilator. He can also use both Solar Lance and Orbital Strike, which were mutually exclusive in the campaign.
  • For Raynor: a structure example, his Bunkers have both the Shrike Turret and the Reinforced Bunker upgrades (the full package is called Battle Bunkers with 50 more hitpoints compared to the campaign's Reinforced Bunkers). Those upgrades are mutually exclusive in the campaign and not interchangable. Adding to that, Raynor also have access to the multiplayer upgrades which increase Bunker capacity and structure armor by 2 (the capacity upgrade is in the campaign, but not armor).
  • For Stetmann: His Mecha Battlecarrier Lords combine the capital ships of all three factions. Functionally, they fight like Brood Lords, but can also launch Interceptors like Carriers and are equipped with the Battlecruiser's Yamato Cannon.
• Alternate Timeline: The mode uses Loose Canon so the developers don't have to worry about contradicting or conforming to lore in designing missions and commanders. This is used to Hand Wave how characters who are chronologically dead by Legacy of the Void are able to take part in Co-op, which (depending on the exact mission) takes place during Legacy of the Void. Tychus' teaser pretty much spells out this is a What If? scenario.
• And Now for Someone Completely Different: A villainous example, the map "Malwarfare" is the only one where your enemy isn't Amon or one of his minions. Instead the enemy is a rogue Tal'darim AI inside the Purifer data network.
• Anti-Frustration Features:
  • Battlefield notifications are shared across both players, so if one bumps into difficult situations like cloaked units or Hybrids, the other automatically knows as well. Likewise, many commander abilities have global notifications, like Karax's Chrono Boost or Abathur's Mend, to let one know when the other is using them.
  • All commanders can build on creep, which means Zerg allies won't get in the way of base building.
  • Commanders with top bar calldowns will be notified when their abilities come off cooldown, when their energy hits its cap, or when their charges max out. The notifications are not immediate, however, and will only play after said abilities have been ready for a while and haven't been used yet, so that the player won't forget about them.
  • When an enemy or allied unit is moving through the map, its travel path is marked on the minimap so you can intercept enemies or clear the way for an ally.
  • The destructible rocks that block expansions on some maps are designated as enemies, thus units and automated defenses like turrets will auto-attack them on sight and clear them out without needing to be told to.
  • Mobile hazard Mutators, like Purifier Beam or Blizzard, are variably set to not move through your base and expansions, or if they do they'll "deactivate" while moving through them, so that your base structures and your workers (at least within a specific radius) will be safe.
  • The game will prompt you twice when you try to activate Prestige mode, so that you won't reset your level by mistake. You're also not forced to use your new Prestige as you level commanders back up, which is critical since some Prestiges only affect units and abilities that the commander has to earn.
• Artificial Brilliance: After complaints that the mode was too easy even on Brutal, Blizzard stepped it up in Patch 3.2. Now AI enemies use randomized unit combinations, they make use of casters and cloaked units, and if you're facing Terrans they will send Ghosts to nuke your base into the void if you don't stop them.
• Ascended Meme: Several strategies that are prominent in melee are integrated into some commanders' playstyles here.
  • MMM (Marines, Marauders, and Medivacs) have been a staple Terran strategy since Wings of Liberty. Raynor's focus on infantry units means that MMM (just with Medics instead of Medivacs) is his go-to strategy.
  • Mengsk's Troopers can build Supply Bunkers themselves, they can work together to build them faster, and he can call down fully loaded Supply Bunkers anywhere he wants. Coupled with the fact Troopers are rather fragile, and Mengsk players are encouraged to bunker rush the opponent and can do so very efficiently.
  • Zagara's Swarmlings mutate almost instantly and three at a time, making the early-game Zergling Rush not just viable for her, but a selling point of playing her.
  • Karax not only has Photon Cannons and Shield Batteries, but with a Talent they construct instantly. Combined with Energizers that project power fields, and Karax can cannon rush enemies to devastating effect.
• Attack Reflector: The Double-Edged mutator causes player units to take damage equal to the damage they deal. The reflected damage is healed back over time, though. Similarly, the Diffusion mutator causes half the damage dealt to an enemy to be evenly spread across all nearby units, including yours.
• Auto-Revive: The aptly-named Just Die! mutator, which causes enemies to respawn on the spot once when killed. Including mission objectives.
• Awesome, but Impractical: Capital units in general. Most commanders have a powerful high-tier unit that is a general all-around powerhouse, but their high costs generally makes producing them a slog as they don't snowball fast enough, and generally don't have the DPS to justify the costs. Unless these units have an incredibly powerful, cannot-be-ignored ability, you are generally better off using the other units in a commander's kit unless a very niche combination of units is demanded for a tricky Mutation.
• Badass Boast: Each commander has several of these that they will say when defeating an enemy wave or completing an objective. They also have victory quotes they may say at the end of a mission instead of your Mission Control speaking.
• Balance Buff: Aside from the expected buffs to commanders that has occurred over time with patches, a lot of mechanics are buffed from the campaign and melee play to be more viable here.
  • Hero units that lacked an anti-air attack, like Alarak and Zeratul, have one here.
  • Similarly, many Heroes have significantly higher health than before due to the maps now being balanced around huge armies being in play, rather than how most Hero Unit centric missions were smaller in scope.
  • Swann doesn't use infantry units and can't build Barracks, his Factory is his default unit production building. To allow him to still build one when players would normally build Barracks, his Factory costs no vespene.
  • Abathur doesn't make Zerglings or a Spawning Pool, his base combat unit is the Roach. They have their vespene cost removed to allow him to get troops out earlier, though they have a higher mineral cost and build time to compensate that he can get them out earlier.
  • Vorazun's Dark Templar have higher shields and lower vespene cost to make using them more practical.
  • Because they wouldn't have Detector units otherwise, Vorazun's Oracles and Alarak's Havocs are their Detectors. For the same reason Stukov's Brood Queens have an ability to turn an allied unit into a Detector for a few minutes^note Unlike Vorazun and Alarak, Stukov can still morph Overseers however.
  • Since his calldowns are a critical part of his gameplay, Karax can upgrade the Spear of Adun for faster energy regeneration and his Orbital Strike and Solar Lance can be upgraded with support effects they didn't have in the campaign.
  • Mengsk's Royal Guard/Elite Guard units were just renamed mercenary-type units in Heart of the Swarm, the same as the base unit just with higher HP and attack power. They're upgraded here to have powerful support abilities.
  • Artanis' Deploy Power Field is an upgrade of the Deploy Pylon ability in the campaign, just minus the physical Pylon.
  • Vorazun's Dark Pylons in the campaign were just normal Pylons with a Nerazim skin; here they cast a cloaking field. Like Artanis's Deploy Power Field, the calldown is also a straight upgrade to Deploy Pylon.
• Breakout Character: Egon Stetmann was pretty much a background decoration in Wings of Liberty. He returned here as Mission Control for "Mist Opportunities", revealing he had been marooned in Bel'shir since the Terran campaign, got addicted to terrazine, and become a kooky Mad Scientist whose insanity is Played for Laughs. He became far more popular with fans for this depiction, and as a result got added as a playable commander later. He's also the focus of a tie-in comic series that provides background for Stetmann's "Mecha Swarm".
• The Bus Came Back:
  • Graven Hill, Egon Stetmann, and Donny Vermillion, haven't been seen since Wings of Liberty; they act as Mission Control in missions here, and Stetmann even got to be playable.
  • The Kimeran Pirates, last mentioned in the Frontline graphic novels that predated the trilogy's release, feature in "Rifts to Korhal".
  • Protoss Scouts were removed from the game and only available to AI enemies, even in the Legacy of the Void campaign. Fenix finally lets players use them again.
• Call-Back
  • Raynor can summon a squadron of Dusk Wings mercenary Banshees or the Hyperion battlecruiser, referring to when he invoked a Gunship Rescue with Banshees to save General Warfield and to escape Mar Sara, respectively.
  • Swann is packing the Drakken Laser Drill and the Flaming Betty perdition turret from Wings of Liberty.
  • Han and Horner primarily focus on large amounts of space fighters, in reference to the Heart of the Swarm mission "With Friends Like These" where the two fought each other while using only spacecraft.
  • Tychus' ultimate while commandeering the Odin is "The Big Red Button"; just like in Wings of Liberty, it launches a nuke. His base gameplay concept of a team of heroes is taken directly from Belly of the Beast.
  • Mengsk' Contaminated Strike and Nuclear Annihilation reference the Ultralisk evolution mission in Heart of the Swarm, where the Dominion was researching chemical weapons and experimental nuclear warheads. His deployment of elite Royal Guard forces is based on his behavior in the last missions of the same game.
  • One of Kerrigan's Prestiges swaps her Leaping Strike and Psionic Shift abilities for Kinetic Blast and Crushing Grip, the abilities she had in Heart of the Swarm that were alternates for those two abilities in her skill tree. She even reuses her human model from the early missions of the campaign when this Prestige is active.
  • Zagara specializes in Banelings and Scourge, spotlight units in her Heart of the Swarm mission chain.
  • Stukov is able to summon the UED flagship Aleksander, apparently recovered and infested. He comments when calling it in that "[he's] glad Gerard never saw it like this."
  • Dehaka can summon Expies of the Zerus pack leaders as calldowns, and references in his lines when doing so that they've taken over the packs of the previous leaders they are expies of.
  • Stetmann may randomly referred to one of his harvesting bots as "Gary" in "Mist Opportunities". When he became a playable commander, Gary became Stetmann's Robot Buddy Hero Unit.
  • Karax's focus on automated defenses are an expansion of his skillset as a Hero Unit in Legacy of the Void, where he could create a temporary Photon Cannon and projected a power field that also vastly increased the production speeds of any structures inside it. His Energizers inherit his Reclamation ability to take command of mechanical enemies, though for balance reasons it is only temporary.
  • Alarak's Empower Me ultimate is a reference to his Rak'shir duel with Ma'lash; just like there, Alarak gains power from having nearby allies to provide him psionic support.
  • Fenix can deploy in a Dragoon body, just like his original namesake. He even says "I am a Dragoon once more!" when doing so. His Purifier heroes are all important Protoss characters who died or are implied to have died in past releases, now converted into AI personalities just like Fenix was. His Akhundelar Prestige turns him into a short-lived but extremely powerful calldown instead of a normal hero unit, just as he was in Legacy of the Void.
  • Zeratul's unique mechanic has him searching for fragments of the Xel'Naga artifact, similar to how he spent time looking for information on the prophecy.
• Call-Forward: Some characters' abilities reference Covert Ops, which takes place after Legacy of the Void when Co-op Mode takes place.
  • Nova and her squad are a whole-part reference to Covert Ops; Nova has the same abilities as in the mission pack, her unit and buildings have the same skins and abilities, and she has the Griffon, her personal transport in the mission pack.
  • Horner's ability to call in the Dominion fleet to strafe an area is from Covert Ops where he allowed Nova to do the same thing in a mission.
  • In an intentionally ironic instance, General Davis is the Big Bad of Covert Ops who was trying to dethrone Valerian. Here she acts as Mission Control for "Parts and Parcel", where she's vocal about her disgust for Moebius Corps betraying the Dominion and Valerian's trust in them.
  • Another one for Davis, in "Parts and Parcel", she steals a prototype mech called the Balius from Moebius Corps. In Covert Ops, she (with her crew) steals another one called the Xanthos from the Dominion. General Carolina Davis sure likes to steal experimental mechs. ^note In the Map Editor, the Balius is called "Archangel Xanthos Experimental" so this is very likely not a coincidence (aside of the fact that both names came from a pair of immortal horses from the Greek Mythology).
  • Mengsk's base units are Dominion Troopers, which were the forces of the Defenders of Man that Davis commands in Covert Ops.
• Canon Immigrant:
  • Sgt. Hammer, Rosa Morales the medic and Miles "Blaze" Lewis the Firebat (one of Tychus's frontliners) appeared as Original Generation characters in Heroes of the Storm before becoming canon via this mode (Loose Canon notwithstanding).
  • Zig-Zagged with Probius the Protoss Worker Unit. While he is first identified by name in this mode, Word of God is that his actual first appearance was in the Legacy of the Void opening cinematic.
• Cast from Money: The Microtransactions mutator causes every order you give to your units to spend resources proportionate to that unit's cost. And don't think you can get away with using hero units or calldowns to bypass the mutator - they also get taxed, often much more heavily than normal units. Fortunately, having no resources will allow you to command your units for free.
• Continuity Snarl: A few commanders have access to technologies that wasn't available during the actual war itself. Certain ones are the Continuity Snarls themselves just for being there.
  • Nova can somehow make use of the Griffin as part of her calldowns, despite it only being granted to her by Valerian when she's acting as his agent after the war has ended.
  • Despite running on Loose Canon, dialogue from many Mission Control NPCs had always made it clear that Valerian Mengsk is the current sitting Emperor, meaning that Arcturus either died as he did at the end of Heart of the Swarm, or was otherwise removed from office. Then Arcturus himself became a playable commander, still being the Emperor, but nobody else acknowledges this.
• Chest Burster: The "Alien Incubation" mutator causes all enemy units to spawn Broodlings when killed. "Walking Infested" causes them to spawn Infested Terrans instead.
• Color-Coded Armies: Each commander has their own personal unit colors.
• The Computer Is a Cheating Bastard: While enemies generally play fair with abilities, there is one exception: Terran enemies can use Scanner Sweep without an Orbital Command if you hit them with a cloaked army.
  • The enemy attack waves are not built, but instead are air-dropped/warped in automatically in certain locations on the map (usually deep in an enemy encampment). The obvious reason for doing this is to ensure the AI is never in a position where it cannot have units to defend itself or attack you (as otherwise you'd just wait around in certain missions until the game ended).
  • In the Dead of Night mission, the AI can decide to use Hunterlings during the first mission. The player on the left resource base must then build defenses behind their supply line or staff it with units as the Hunterlings will frequently jump over the gap and attack your workers directly.
  • In Void Launch, the first enemy attack wave can decide not to attack the base from the center and instead attack the expansions if they've been taken. This can immediately force you to split your forces between taking down the defended launch ships, and defending your base expansion which will likely be wiped out early-game by the Hybrid. The fact that the AI even knows you've done this and only ever does this when you've taken it implies it is notified you've done this despite not having vision of your base.
  • When Zeratul was initially released, the Miner Evacuation mission had a bug where the infested would be able to see Zeratul's base and would immediately go to attack it the moment the mission started before either player could defend themselves (certain characters have no calldown abilities or defenses to use right when the game starts), leading to the players being defeated before the mission began. Thankfully this was patched out.
• Confusion Fu: The Power Overwhelming mutator gives all enemy units the ability to randomly cast various abilities, resulting in things like Zerglings casting Psionic Storm or Fungal Growth on your army out of nowhere.
• Cosmetic Award: Past the Mastery capstone of 90, players no longer gain any further gameplay benefit, and the only incentives for continuing the grind are some unique sprays and emotes upon reaching specific Ascension levels.
• Crosshair Aware: Map objectives and bosses with area-of-effect attacks will usually have the target area clearly marked for players a few seconds before they go off. Ditto for damaging mutators like Orbital Strike and Going Nuclear.
• Deadpan Snarker: Aurana, the Mission Control for Malwarfare, stands out for being exceptionally sassy for a Protoss (well, a Purifier anyway). Doubles as a Danger Deadpan since she'll continue snarking coolly while being attacked by hostile forces throughout the mission.
  "My work here is almost finished. If you can believe it."
• Death from Above:
  • A lot of calldown abilities summon reinforcements to drop on the battle field or command weapon barrages from orbit. Zagara invokes the trope by name when using Drop Pods, which is the former such ability that spawns Roaches at the target location.
  • The "Going Nuclear" mutator causes nukes to be dropped around the map at random. The "Orbital Strike" mutator causes random orbital strikes to fire on the map. "Purifier Beam" has a Purifier Beam continuously moving across the map.
  • Beating Scythe of Amon shows the Voidshade Hybrid's crystal being destroyed by orbital attacks from the commanders, with the exact attacks varying depending on the race of the players' commanders (Terrans barrage it with either Yamato Cannons or nukes, Zerg unleash a hail of Scourges, and Protoss deploy a Purifier Beam).
• Death Is a Slap on the Wrist: All commanders with a Hero Unit will automatically revive at their base 60 seconds after dying, though there are exceptions.
  • If Fenix's current shell body is destroyed it takes time to rebuild it, but he can deploy in a new one while it is repaired.
  • Tychus spawns for free after a few minutes like all heroes, but if he dies the player has to re-recruit him from Joeyray's Bar like any other Outlaw. Or, they can summon the Odin, and Tychus pops out when its timed life expires.
  • Dehaka has a 90-second respawn timer, but he can eat Drones to respawn faster, rendering the timer irrelevant in most cases if he doesn't mind cutting down his economy slightly.
• Defeat Equals Explosion: Slain enemy units will blow up when they die while the "Self-Destruction" mutation is active. Hybrids in particular have their own flavor, "Mutually-Assured Destruction", where they will explode like nukes when killed. If your units are standing too close to them when they die, they'll most likely bite it as well.
• Developer's Foresight:
  • If you take Alarak into "Chain of Ascension", Ji'nara has different dialogue as Mission Control, since she's his subordinate. Additionally, Alarak's rank as a Hero Unit is normally "Highlord", but since in-story he's merely serving as a supplicant for Ji'nara, his rank is changed to "Challenger" in this mission.
  • Lyrak will have a unique greeting for Vorazun at the start of "Scythe of Amon", as Lyrak scouted on her orders for the Nerazim.
  • After Stetmann was made playable, if you take him into "Mist Opportunities" where he's Mission Control, his dialogue is framed as him talking to himself or Gary. He also will no longer imply one of the harvesting bots he sent out is Gary, since he'd be busy fighting rather than harvesting Terrazine.
  • Also in "Mist Opportunities", the harvesting bots are considered ground units by the game rather than air, so that the enemy can be a threat to the bots no mater what unit composition is chosen.
  • Averted entirely in the case of Arcturus Mengsk, where despite him still being alive as the sitting Emperor, nobody will ever address him as such when played on maps with Dominion personnel, like Void Thrashing or Rifts to Korhal, the latter of which is basically set on his front lawn. It's even more of a Continuity Snarl when those same NPCs also acknowledge Valerian as the current ruler instead of his father.
• Discard and Draw: Patch 5.0 introduced the Prestige system, where the player with a maxed-out (i.e. level 15) commander can opt to reset their leveling progression and grind back up to 15 again, up to three times. Doing so unlocks one of three Prestige modifiers that significantly alter how they play, usually in the form of one substantial buff and the removal/Nerf of another aspect. For example, Karax's "Architect of War" allows his passive support abilities like Chrono Wave and Repair Beam to boost his automated defenses at greater efficiency, but those support abilities no longer work on normal units.
• Difficulty Levels: Same as the single-player campaigns, they go Easy, Normal, Hard, and Brutal. On easier difficulties, aside from enemy forces being smaller and less sophisticated with upgrades and spellcasters, mission objectives are made easier in various ways, such as time limits being adjusted to give players more time to prepare or having to hold off the enemy for less time, objective-specific units and structures have more HP if they're allied and less if they're the enemy, and if the mission demands the player not let too many such allies die or too many enemies survive, those limits will be higher. A patch added Brutal+, with the stipulation that players must be Level 15 in a commander or in a party to play it. Beyond that are Brutal+ difficulties with a numerical designation, which add random Mutators to the mission and are only allowed if you're in a party; the interface directly warns you to only select these difficulties if you like losing a lot.
• Divergent Character Evolution: The tech trees of the commanders differ greatly, so while they may command the same race, they play very differently. The addition of Prestiges introduces divergent playstyles within the same commander, as the tweaks to their base kit means that two different prestiges can cause a commander to play entirely differently.
• Early Game Hell: While missions often take it easy on the players at the beginning to give them a chance to ramp up, some missions are less merciful than others:
  • Rifts to Korhal is somewhat infamous for throwing an attack wave at you two minutes into the mission, at which point heroes not named Dehaka haven't even spawned yet and most commanders won't have enough army units to deal with it on higher difficulties if playing their usual builds. Once that attack wave is down, though, the rest of the mission becomes more manageable.
  • Chain of Ascension makes you fight both an early pack of Hybrid, especially if you push too quickly, and an abnormally strong early attack wave. Ramping up quickly or using early calldowns efficiently is essential on this map, not helped by the fact that the expansions on this map are guarded by enemies, making it difficult to expand early on.
  • Scythe of Amon and Part and Parcel have very stingy time limits on harder difficulties, with Scythe of Amon's targets for buying additional time being heavily defended. The time given at the start of these missions is very short, requiring immediate action.
• Early-Installment Weirdness: Some of the launch commanders have kits that are slightly different from those released later. Prior to the release of Alarak, commanders that take to the field as Hero Units (i.e. Kerrigan, Zagara) didn't have a top bar for calldowns, and all of their abilities were handled via the command card. Later Hero Unit commanders have their own top bars that they can use in conjunction with the abilities of their own unit.^note Both Kerrigan and Zagara have abilities that behave more like top-bar ones than normal hero abilities, respectively Kerrigan's Immobilizing Wave and Assimilation Aura, and Zagara's Mass Frenzy and Infested Drop, the latter two not even being centralized on her hero unit itself.
• Elite Mooks: In addition to various regular units from a random race, missions will also pit you against various numbers of Hybrids. As they were in the campaign, Hybrid units are universally tougher than anything the actual enemy composition throws at you. You yourself will also often be provided with significantly more powerful versions of various units, and outright boss monsters of your own.
• Escort Mission:
  • "Mist Opportunities" and "Malwarfare" require commanders to escort an AI ally through the map and defend them from enemies. "Scythe of Amon" has the bonus objective to clear landing areas and flight paths for evacuee shuttles.
  • Subverted with "Part and Parcel" - while the Balius is required to spawn and fight the Moebius Hybrid, it will simply return to base if it takes fatal damage at any point, so escorting it isn't technically required. Even if it gets taken out before reaching the Hybrid cells, the Balius will just head to the cell in flight mode, break it open, and fly back for repairs.
• Faction Calculus: One for each faction.
  • Terran: Raynor (Horde), Swann (Balanced), Nova and Tychus (Powerhouse), the Horners (Cannon/Powerhouse) and Mengsk (Subversive).
  • Protoss: Artanis and Fenix (Powerhouse), Karax (Balanced), Vorazun and Zeratul (Subversive), and Alarak (Cannon).
  • Zerg: Kerrigan (Balanced), Zagara and Stettman (Subversive), Abathur and Dehaka (Powerhouse), and Stukov (Horde).
• Friendly Fireproof: Played With. Any forms of splash damage friendly fire, from both attacks (like from Siege Tanks) and abilities (like psi-storms and nukes), are disabled, even where they normally have it, and it's not possible to use single-target offensive abilities (like Yamato cannons) on friendly targets. The only exception is basic attacks: players are still able to manually order to attack their or ally's units and buildings (except with some units which uses abilities instead of the normal attacks, like Swann's laser drill).
• Gameplay and Story Segregation: There are actually quite a few examples, and commander-specific ones can be found on this page.
  • Any commander and any unit is able to psionically support Ji'nara in Rak'shir, not just Protoss.
  • Stukov is capable of asserting control over lesser infested Terrans, but can't do so to get an easy win on Dead of Night or Miner Evacuation. He even has an unused voice line noting this.
• Hero Unit: Certain commanders take to the field as powerful units that the player can command. Tychus in particular fields a small crew of nothing but Hero Units. Amon's Hybrid also take on many aspects of this trope, such as the Heroic unit type, higher health to damage ratio and variety of abilities.
  • While the Heroes From the Storm mutator is active, Amon himself gets a few, with every attack wave being led by an enemy version of a commander. These "evil" Hero Units have modified appearances from your own, and may possess abilities that yours don't have.
• Hold the Line: "Temple of the Past" and "Void Launch" require the commanders to defend objective points from waves of enemies for a period of time. "Miner Evacuation" has the commanders defending transports, but they have to fight their way to them and then defend them from enemies. "Dead of Night" has players focus on defending their bases at night, but they can attack the enemy during the day and have to destroy them to win, they can't just defend.
• Holiday Mode: Certain special seasonal Mutations are rolled out for holidays:
  • Christmas rolls out a Mutation on Void Launch where gifts spawn around the map and can be collected by players and Amon alike. Gifts claimed by players give various benefits, while ones claimed by Amon's forces make the mission harder.
  • For American Thanksgiving, the Mutation takes place on Oblivion Express, and forces players to share supply and kill turkeys to expand their collective supply cap... although the turkeys will most certainly fight back. Oh, and you periodically get attacked by Infested Turkeys that can level bases in seconds, and eventually fight a giant turkey boss.
  • April Fools' Day has the two commanders fighting each other. Given the amount of Purposely Overpowered stuff in Co-op Mode, such games tend to be comically short unless both players make a gentleman's agreement to not cheese each other.
  • Halloween had a unique Mutation on Rifts to Korhal where your units' vision is almost completely taken away in areas where you're not looking with your camera, and your base contains a candy bowl that must be filled using minerals to appease trick-or-treating civilians. If the civilians aren't given candy quickly enough, they turn into random enemy units.
  • The Lunar New Year mutation has red envelopes containing mineral and gas spawning around the map for players to pick up. On the flip side, enemies will shoot off damaging fireworks when killed.
• Increasingly Lethal Enemy:
  • The Avenger mutator turns every enemy into one. Whenever a unit is killed, all other nearby enemies gain a stacking bonus to pretty much everything. This potentially turns even a lowly Marine or Zergling into a Boss in Mook Clothing if enough things die around them, and let's not even get started on Hybrids.
  • The Transmutation mutator gives enemies a chance to evolve into stronger units every time they deal damage (which becomes a guaranteed evolution if they actually kill a unit). If handled poorly, a wave of Zerglings can very easily evolve out of control and become a pack of Hybrids with this mutator active.
  • In Dead of Night, the further the turns continue, the worse things get. On Night 3 and later, either Stanks or Nydus Worms will spawn, and each subsequent night will send out another one. Slowly, but surely, the danger they pose will begin overwhelming the players.
• Instakill Mook:
  • Propagators from the aforementioned Mutator will instantly kill any unit they "attack" and spawn another Propagator in that unit's place. This even affects heroes and buildings.
  • Death Grip Crystals, summoned by the Void Slivers on Scythe of Amon, will stun a number of units for a duration and destroy them once the stun ends unless the Crystal is destroyed before then.
  • StarCraft I Queens will appear as enemies in Miner Evacuation and certain Zerg compositions, and still have the Spawn Broodling ability. Downplayed as the AI's programming means they'll only use the ability on Siege Tanks specifically.
• Interface Screw:
  • The "Darkness" mutator keeps the fog of war permanently on, preventing players from seeing where attack waves are coming from and where objectives are.
  • The "Vertigo" mutator randomly changes the player's camera angle.
• Invisibility: Par for the course. Certain commanders have access to some form of invisible units, such as Raynor's banshees and Dusk Wings, or Nova's own Hero Unit and her Spec Ops Ghosts, and most Zerg units can still burrow. Amon himself also has a few of these invisible units in nearly every composition. As usual, most of them can be revealed by detectors, though certain units or commanders may have access to Super Cloak, which is usually temporary, but cannot be seen through.
  • The "We Move Unseen" Mutation gives every enemy unit cloak. Better hope your detection game is strong.
• It's Raining Men: Both Cradle of Death and Temple of the Past have enemies being deployed through drop pods directly onto the defense objectives. Meanwhile, the Aggressive Deployment mutator has enemy waves periodically being dumped on the players' heads throughout the mission.
• Jack of All Stats:
  • As the roster filled out with more specialized and unique commanders, the base three developed into this — Kerrigan, Raynor, and Artanis, all have well-rounded armies that can handle most enemy compositions well, each have their own traits to reinforce armies quickly and mass large numbers of units, and their ultimate abilities are simple to use and do decent damage. On the flip side, they're also not particularly standout in any field — without skill on the player's part they can struggle against certain enemy compositions and objectives that counter their core army compositions, and the player may need to pick an unorthodox build to cover an ally's shortcomings in their kit.
  • With the introduction of prestiges, a given commander's default profile is this for their kit, as it allows you access to their entire usual repertoire. While they won't be having access to any significant buffs, they also won't be having any penalties or limitations either, allowing you to have much more flexibility in different situations where some of their prestiges might struggle to progress at all.
• Kill Sat: Karax's ultimate ability, Purifier Beam, is this. While the mutation of the same name is active, Amon gains a few of these as well, which will slowly move towards your units and expansions (but cannot enter the latter due to an Anti-Frustration Feature).
• Later-Installment Weirdness: Later commanders got very creative and unique. The base trio of Raynor, Kerrigan, and Artanis, are essentially trimmed-down versions of the campaign tech trees and abilities, while the likes of Tychus, Dehaka, and Zeratul, have entirely different mechanics from anything seen prior to their release.
• Loose Canon: While the missions are ostensibly set during the campaign of Legacy of the Void, there's no way that, say, Dehaka and Nova were on Shakuras helping to fight Amon's forces, or Zagara and Vorazun went to Kaldir to destroy Amon's troop shuttles. invoked Word of God is that they don't pay attention to continuity or story when developing missions, as trying to do so would just hinder the types of missions they could create. It's also the mentality they use to justify the inclusion of canonically dead characters like Tychus and Zeratul as commanders.
• Macross Missile Massacre:
  • In Part and Parcel, the Balius destroys the Hybrid containment cells with a flurry of missiles.
  • The Missile Command mutator puts you on the receiving end of one, firing a constant stream of missiles at your structures throughout the mission and forcing you to shoot them down to avoid losing your base.
  • Mengsk's Nuclear Annhilation ability and Artanis's Solar Bombardment ability are this.
• Made of Explodium: Several mutators have enemies explode to deal damage on death. By far the most spectacular, though, is Mutually Assured Destruction, which causes Hybrids to go up in a nuclear explosion on death.
  • When Han's reapers die, they drop a number of charges and detonate the area around them.
• Magikarp Power:
  • As they level up and learn Talents, each commanders gets more upgrades and units available for production. A Level 15 commander plays very differently from a Level 1 one, and is much more powerful. In addition, beyond Level 15, all commanders gain access to a Mastery skill tree, allowing them to make specific aspects of their kit even better.
  • Some commanders are plagued with an agonizingly glacial and weak early game with a very slow ramp, like Swann and Karax. If given the time to build and tech up, however, they tend to be obscenely powerful in the late-game, once they've managed to hit their stride and amassed a sizable army.
• Mechanically Unusual Fighter: In general, all commanders have various quirks that make them differ from the multiplayer versions of their races, giving them each a unique playstyle.
• Mirror Match: The Heroes From the Storm Mutator adds Evil Counterparts of given commanders to attack waves, including those who don't normally have a Hero Unit such as Karax. This trope applies if the spawned hero unit is the same as the commander you're playing as.
• Mook Maker:
  • One of the Moebius Hybrids' abilities in "Part and Parcel" allows it to spawn a small army of units on top of the players fighting it.
  • Void Rifts and Void Reanimators from the eponymous mutators will constantly spawn units to harass your base. Void Rifts spit out a steady stream of units, while Void Reanimators will continuously revive dead ones for as long as they're alive. Void Rifts are also spawned by the Void Slivers in "Scythe of Amon", but mercifully the units spawned from them won't attack your base.
  • Rifts that surround the Void Sliver's in Scythe of Amon will continuously spit out new units at a regular pace until destroyed, but when destroyed will respawn later if the Void Sliver isn't destroyed. As such, if you fail to completely destroy a sliver, it's likely the defenses around it will be back to full power before you try again.
• Night of the Living Mooks: "Dead of Night" and "Miner Evacuation" both have players fighting huge waves of Infested Terrans, and the Outbreak mutator will continuously spawn Infested to harass your base. On the players' side, Stukov fights by swarming his enemies with Infested.
• Notice This: Due to them being exceptionally dangerous enemies if not handled, Propagators and Boom Bots are marked on the minimap with "!" icons even through the fog of war.
• Nuke 'em: Terran commanders come with plenty of nukes, but Amon isn't averse to using these either:
  • Terrans on Brutal difficulty will sneak Ghosts into your base to drop nuclear strikes on it. This is particularly common on Oblivion Express, where enemy bases are everywhere and you're smack-dab in the middle of the map.
  • Nukes show up in several Mutators. Going Nuclear is the simplest, dropping nukes periodically around the map (generally targeting your units specifically), Missile Command eventually throws nuclear missiles at your base on higher difficulties, Boom Bots will nuke your base/army if not disarmed before reaching it, and Mutually Assured Destruction turns Hybrids into nuclear Action Bombs.
  • If a player used a Terran commander on Scythe of Amon, the "victory" cutscene may show the Voidshade Hybrid being nuked.
• Obvious Rule Patch:
  • When Nova was released, her Strike Goliaths' ability to stun air units also applied to airborne mission objectives like the pirate ship on "Rifts to Korhal" and the shuttles in "Void Launch". As you might expect, this was quickly patched out for making these objectives into a complete joke.
  • The "Laser Drill" mutator gives Amon's army a Drakken Laser Drill much like Swann's, which can attack player units from infinite range. However, players quickly found that they could cheese the mutator by simply destroying the laser drill, rendering it a non-issue for the rest of the mission. It didn't take long for the mutator to be patched so that the laser drill respawns a few minutes after being killed.
  • Early on, players found that the combination of Artanis and Raynor can easily cheese Lock and Load by simply deploying units onto the locks behind enemy lines for a quick win. The units guarding the locks will now move to attack player units that stand on them.
• One-Steve Limit: Players can't play as the same commander.
• Overrated and Underleveled: The Balius. According to General Davis, it's the only thing that can stop the cybernetic Hybrid in Parts and Parcel. In practice, the Balius's pitiful DPS and relatively meagre 1500 health (compared to equally sized superunits such as the Apocalisk, Archangel, Odin, and Stank) make it little more than scenery in the actual fights themselves.
• The Plague: The Black Death mutator gives enemy units a chance to carry a plague debuff that spreads to nearby player units when the host dies; infected player units can then spread it to other units on death, and so on.
• Play as a Boss: Several commanders have access to what are effectively boss units they can summon as a powerful calldown ability, of particular note are Dehaka, who can call in three different Primal Packleaders, each one a Moveset Clone of another primal zerg that served as a boss fight in the Zerus portion of Heart Of The Swarm and Tychus, of course, brings the Odin with him, which served as the Final boss of the same campaign.
• Recursive Adaptation: Many abilities of the commanders appeared for them in Heroes of the Storm and have now been re-adapted for this mode. The developers have even acknowledged this — Abathur was to be able to have Symbiotes to latch onto units to give them special abilities like he can do in Heroes, but they realized that type of mechanic works better in a MOBA like Heroes than in an RTS like StarCraft, where players are commanding dozens of units at once and probably won't want to or can't keep track of the Symbiote. As such, the Symbiote was made into a passive upgrade for Abathur's ultimate evolutions. His Toxic Nests were, however, carried over wholesale.
  • Though the exact mechanics are different, Raynor's Dusk Wings and Hyperion calldowns previously appeared as his Heroic abilities in Heroes. Horner's Call in the Fleet calldown, on the other hand, recycles the mechanics of Raynor's Hyperion Heroic.
  • All of Zagara's abilities save for Mass Frenzy previously appeared as part of her kit in Heroes, although they were rebalanced for the Co-op Missions environment.
  • Kerrigan retains her Heroes version's ability to gain temporary shields when dealing damage.
• Revenue-Enhancing Devices: On free-to-play accounts, only Artanis, Raynor, and Kerrigan are playable. Buying the game unlocks Vorazun, Swann, Zagara, and Karax for play, and if you want to level any of the others beyond 5, you'll have to shell out some more money. Note that none of the commanders are designed to be inherently better than any other; you simply have less variety in playstyles.
• Secret A.I. Moves:
  • "Evil" hero units spawned by the Heroes From the Storm mutator tend to have abilities that your own don't, such as Kerrigan having access to Apocalypse, or Dehaka capable of using Mend. These abilities are taken from their campaign counterparts instead of the ones you actually control.
  • Certain units in Amon's army also have different abilities from the versions used by the players (with most of them being taken from multiplayer). For example, enemy Corruptors can use Caustic Spray while Zagara's cannot.
• Serial Escalation: Terran Commanders and their various increasingly over-the-top Nukes. Raynor doesn't have access to nukes at all and Swann's Pulse Cannon only copies the Nuke's reticle for a laser attack with high area damage, then Nova fires off an actual nuclear missile. Mira Han drops a satellite that squashes everything under it then detonates like a Nuke. Tychus's Odin comes with an even bigger Nuke that can one-shot lesser Hybrid, and finally Mengsk forgoes all subtlety and dumps 40 tactical nukes followed by a single big nuke.
• Shout-Out: Weekly mutation names and mutator combos are full of these.
  • Train of the Dead
  • War Is Hell
  • Burning Legion
  • World on Fire
  • Fright Night
  • Rumble in the Jungle
  • Survival of the Fittest
  • Blast from the Past
  • The Injustice League
  • The Quick and the Dead. A later mutation reuses the reference as "The Quick and the Undead".
  • Watch the Skies
  • Death and Taxes
  • Double Trouble
  • By Fire Be Purged
  • Dance Dance Evolution
  • The League of Vermillains
  • What We Do in the Shadows
  • Bubble Pop
  • Hello My Old Friend
  • Enter the Nexus
  • Sudden but Inevitable
  • The "Kill Bots" mutator makes you fight invulnerable kill bots with a preset kill limit, which are defeated by sending your units at them until they reach their limit and shut down.
• Skill Gate Characters: The base three commanders Raynor, Kerrigan, and Artanis. Their gameplay is very similar to the single-player campaigns, all three have powerful basic but functional armies with abilities that are either passive or autocasting, and their Talents and abilities lean them towards large numbers of cheap units that are difficult to kill and/or can quickly be replaced. This means that players familiar with the campaigns can adapt quickly and don't need to worry about strategy beyond massing a large deathball of units and Attack-moving them around the map. While this can work well enough on Normal and even Hard, higher difficulties will quickly stomp on players that try that kind of simple playstyle, encouraging them to mix in their support units and learn to micro their army and utilize proper unit compositions. Other commanders have higher skill ceilings and more unique mechanics, and the game warns you they're meant for more experienced players.
• Summon Bigger Fish: A good number of commanders have calldowns that summon powerful units to fight for them temporarily, such as Raynor calling down the Hyperion, Stukov summoning an Apocalisk, or Dehaka calling in his Pack Leaders.
• Timed Mission: All Co-op missions are timed in some way or another. Depending on the mission, this can take either the form of a hard timer that automatically makes you lose if it runs out, a soft timer in the form of a defense objective that causes the mission to fail if its life reaches 0 (e.g. "Void Thrashing"), or a certain amount of time you have to hold out for. "Chain of Ascension" and "Dead of Night" don't technically have timers, but your resources are limited and the enemy attacks will eventually become so ruthless that you can't hold out anymore.
  • Theoretically the only mission that isn't timed is the "Lock and Load" mission if you manage to keep one lock from ever being taken by either faction, and then defend the remaining locks while taking control of them. The enemy will continue sending attack waves, but as long as no locks are currently overloading, the mission can continue forever until the player's either quit, defeat themselves, or finally take the last lock.
• Wave-Motion Gun:
  • The Moebius battle station where Cradle of Death takes place is armed with a gigantic main gun. Beating the mission shows the weapon exploding; if you lose, the gun turns toward the camera and fires.
  • The Laser Drill mutator gives Amon a Drakken Laser Drill that attacks player units in vision range of enemies. The Laser Drill is destructible, but automatically rebuilds over time.
• Weather of War: The Twister and Blizzard mutators summon storms that sweep across the map, damaging any player units caught in their path. Enemies are, of course, unaffected.

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