Halo Wars Definitive Edition Full Campaign Walkthrough (Co-op Legendary)

This is a full Legendary co-op run of Halo Wars: Definitive Edition. The walkthrough focuses on clearing every mission while collecting skulls and black boxes, with practical commentary on unit choices, base defense, and mission pacing.

Game Feel and Design Notes

• Halo Wars 1 nails the authentic Halo atmosphere better than its sequel—it has a grittier, darker palette that feels more like a war game
• The menu system mirrors Halo 3's design, and the limited edition originally included a Halo 3 map pack and the Flame Warthog
• Buildings are delivered by large drop ships that split apart and weld together—a cooler visual than the Condor drops in Halo Wars 2
• The developers (Ensemble Studios) made Age of Empires 3 before this, which is why the games share DNA—Age fans will feel at home here
• Rebel base assets appear in multiplayer, tying into the lore that Spartans were originally made for the insurrection, not the Covenant

Campaign Flow

• The run starts on Harvest with fast base rebuilding, early convoy rescues, and quick skull/black box pickups
• Mid-campaign pivots to Arcadia, where the pace spikes and defensive pressure becomes constant
• The Shield World arc introduces sustained Flood combat, multi-faction fights, and larger base networks
• The finale ends with Spirit of Fire repairs and Forge's sacrifice to finish the campaign

Mission Highlights

Mission 1-2: Harvest

• Establish Alpha Base quickly—buildings construct at 10x speed during the tutorial phase
• The first black box is under a bridge near the starting area
• First skull triggers after killing a specific Grunt camp
• Warthogs and Marines carry early pressure; dodge Grunt grenades to keep Forge's Warthog alive
• Destroying the methane refineries takes out the enemy air pads, reducing base harassment

Mission 3: Relic Interior

• Very short mission that can be speedrun in about five minutes once collectibles are secured
• Enemies spawn infinitely from doors—you can farm veterancy here if you want to min-max
• Keep a Marine squad stationed to grab the skull when it spawns; don't "all units" move or you'll pull them away
• Grizzly tanks with two or three stars become extremely effective at destroying Hunters
• The black box is outside the main structure, guarded by Jackals

Mission 4: Arcadia City (Hardest Mission)

Mission 5: Arcadia Outskirts

• The Mega Turret will one-shot your units; approach carefully
• Black box is near the far eastern reactor
• Skull requires killing 5 Wraiths—don't hijack them or the kills won't count
• Spartans can hijack enemy vehicles, which is useful but conflicts with the skull objective
• Station units inside reactors to gain bonus power income

Mission 6: Dome of Light

• Kill 50 Banshees for the skull, which spawns in the back of the warehouse area
• Station the Spartan with the laser in a garrison tower for easy achievement progress
• Wolverines and turrets are essential for the constant air drops
• The first major wave hits hard—have a definitive defensive force ready before pushing
• Upgrade to Wingman and Chaff for Hornets; these upgrades are more impactful in HW1 than HW2

Mission 7: Scarab

• Destroy conduit towers to slow the Scarab's advance
• After 10 conduits, the skull and black box spawn together
• Start with Warthogs for mobility, then pivot to Scorpions and Cobras
• Rhinos underperform here compared to other options
• Cobras can cheese bases from outside turret range by attacking from elevated positions

Mission 8-9: Shield World

• Flood pressure ramps up significantly; missile turrets are recommended against swarms
• Dormant Flood structures can be permanently destroyed during Cleansing waves
• Cleansing waves periodically sweep the map—fly away from them to survive
• The skull requires killing 20 Flood Stalks; sweep the map systematically
• Wolverines are essential for dealing with the constant flying Flood forms

Mission 10: Shield World (Continued)

• Kill 350 Flood Swarms for the skull—this is the most time-consuming objective
• Gremlins (unique unit) are underrated; they chain-stun enemies and can lock down entire groups
• Black box is due north of the base hangar, but you need Hornets to reach it
• Station Wolverines at the corners of the Spirit of Fire to catch Flood on flyby patterns

Mission 11: Reactor Defense

• Reactor defense is a hard fail condition—if the reactor dies, you lose
• The skull requires killing 10 Bomber forms; Vultures are recommended
• You can hijack Locusts to cheese Covenant bases from outside turret range
• There's a spot on a rock where a Locust can sit safely and farm kills indefinitely

Mission 12: Repairs

Skulls and Black Boxes

How They Work

• Black boxes work like skulls in FPS Halo games—hidden collectibles in specific locations
• Skulls are unlocked by accomplishing something (killing specific enemies, hitting kill counts)
• Flying units can pick up both skulls and black boxes
• The game can get buggy with skull spawns; sometimes you'll miss one due to pathing

Mission-Specific Locations

Harvest Missions:

• Black box is under a bridge near the starting area
• Skull triggers after clearing a specific Grunt camp

Relic Interior:

• Keep Marines stationed where the skull will spawn; don't use "all units" or you'll miss it
• Black box is outside, guarded by Jackals

Arcadia City:

• Skull spawns after killing 50 Elites, near where three walkways converge
• You can pick it up with flying units

Arcadia Outskirts:

• Skull requires killing 5 Wraiths (hijacked kills don't count)
• Black box is by the far eastern reactor

Dome of Light:

• Kill 50 Banshees for the skull
• The third reactor position can only be reached by Pelican drop—black box is there

Shield World Missions:

• One skull requires 750 Flood kills—by far the most painful objective
• Another requires killing 20 Flood Stalks—sweep the map systematically
• Black boxes are often at the edge of the map or near hangar doors

Repairs:

• Skull requires destroying 12 Spirit transport ships before they land
• Black box is at the front end of the ship near Captain Cutter's nameplate

Legendary Co-op Tips

Role Distribution

• Split roles: one player holds base defense and economy while the other pushes objectives
• Transfer units constantly to balance power spikes and keep both fronts active
• In co-op, both players can build on shared bases—coordinate who upgrades what
• Set rally points for your partner when making units for them

Economy and Defense

• Build turrets early on missions with repeat air drops—missile turrets specifically for Flood swarms
• Pocket your Heals—you can drop them on cargo pods that aren't under attack to repair them
• On missions with multiple bases, controlling power reactors is critical for tech upgrades
• Garrison Marines in reactors for bonus income

Combat Tactics

• Wolverines and Hawks/Vultures handle air threats and Scarabs far more safely than ground pushes
• Park a unit on critical objectives (reactors, control points, conduits) to avoid soft locks and unlock upgrades faster
• Don't use "all units" commands carelessly—you'll accidentally pull defenders away from objectives
• Use local units selection when you need to move only nearby troops

Unit Management

• Right trigger lets you micro individual units when you have "all units" selected
• You can hijack enemy vehicles with Spartans, but killed enemies won't count for skull objectives
• Flying units can pick up skulls and black boxes
• Warthogs can revive downed Spartans quickly—sacrifice a Warthog to res your heroes if needed

Unit and Tech Priorities

• Early game: Marines, Warthogs, and Flamers for map control and early pickups
• Midgame: Scorpions, Wolverines, and Hawks for flexible responses to Hunters and air
• Late game: Vultures and MAC upgrades for Scarabs, backed by tech-upgraded bases

Specific Unit Notes

Scorpions vs Grizzlies:

• Power Turret Scorpions with Spartans inside are the GG army composition
• In HW1, Grizzlies have a much weaker Canister Shell compared to Scorpions
• This is different from HW2 where the Grizzly has different pop costs

Hornets:

• Best unit for Arcadia City because Hunters and Locusts can't attack air
• Wingman upgrade is huge—more impactful than in HW2
• Chaff Pod upgrade helps survivability significantly

Cobras:

• Can attack bases from outside turret range when positioned on high ground
• Excellent for "cheesing" enemy bases safely

Locusts (Hijacked):

• If placed on certain rocks, they can sit safely and rack up kills
• Use them to destroy bases from long range without taking return fire

Flamers:

• Essential against infantry-heavy Flood sections
• Fully upgraded Flamers slaughter most ground threats

Wolverines:

• Critical for any mission with heavy air presence
• Station them at base corners to intercept flying enemies on approach

Gremlins:

• Underrated unique unit with chain-stun ability
• Can lock down entire enemy groups; no one used them in multiplayer but they were powerful

Spartans:

• Can hijack enemy vehicles, giving you instant combat power
• Put Spartans inside Scorpions for the ultimate late-game combo
• Jerome with the Spartan Laser should be garrisoned in towers for achievement progress

Veterancy and Upgrade Mechanics

Veterancy System

• Units gain stars (veterancy) by killing enemies—stars are more impactful in HW1 than HW2
• A two-star Grizzly noticeably outperforms an unvetted one
• You can farm veterancy by letting enemies spawn infinitely from doors (Relic Interior mission)

Upgrade Philosophy

• HW1 has more unit upgrades than HW2, where most units only have one upgrade
• Rush to T3/T4 when possible for Wingman, Canister Shell, and similar game-changing upgrades
• ODST upgrades require specific tech levels to unlock

Leader Powers

• Anders can heal vehicles with her ability
• Cryo Bomb destroys air units effectively—save it for swarm situations
• MAC Blast is your answer to Scarabs and heavily fortified positions
• Carpet Bomb is useful for clearing grouped enemies but less precise

Story and Character Notes

• Sergeant Forge: A man with a shotgun on a mission; his relationship with Anders provides emotional stakes
• Professor Anders: Her abduction drives the Shield World plot
• Serena (AI): Has attitude; her line about "so we can all die together" captures the desperate tone
• Red Team Spartans: Jerome, Alice, and Douglas—all referenced in Halo Wars 2
• Captain Cutter: His name appears on the Spirit of Fire during the finale mission
• Forge is brought back as a leader in Halo Wars 2 in his Warthog, honoring how players remember him

Lore Details

• The campaign ends with the Spirit of Fire going into cryosleep and becoming "lost with all hands" for 28 years
• This explains why the UNSC in Halo 1 doesn't know about the Flood—the Spirit of Fire crew couldn't report back
• The multiplayer Rebel bases tie into the lore that Spartans were originally made for the insurrection