Halo Wars 2

This achievement is best done with at least one Co-Op partner, but it can definitely be done solo if additional player assistance is not available. This solution will assume that there are two players in the match; should you be playing alone, however, follow the same methodology below and make sure you are playing with Atriox as your Leader.

First thing is first: one player will be playing with Atriox and the other with Captain Cutter. A heavy-hitting, vehicle-based deck for either leader is key for this method. Decks can be modified under the "Decks" tab in the Blitz menu. Please refer below for recommended deck builds before moving onto the actual strategy involved.

Atriox

• Hunters
• Locust
• Assault Elites
• Engineer
• Reaver
• Ironclad Hunters
• Marauder
• Prowling Reaver
• Wraith
• Blisterback
• Ironclad Wraith
• Scarab Assault

Captain Cutter

• Cyclops
• Wolverine
• Nightingale
• Warthog
• Hornet
• Veteran Cyclops
• Archer Missiles
• Kodiak
• Scorpion
• Trooper Hornet
• Vulture
• Close Air Support

With these two decks readied, start the match. Once player control is gained, one player should move to Zone B and the other to Zone C. The strategy that follows is quite simple provided you draw the appropriate cards to pull it off. Remember: you can recycle cards for 5 Energy at any time.

1. Place Kodiak and Blisterback Units on the ridge between Zone B and Zone C.
2. Place Engineer and Nightingale Units on the ridge so they can support/heal your artillery Units.
3. Place Reavers and Wolverines at Zone C.
4. Place Scorpions, Wraiths, Hunters, and Cyclops at Zone B.
5. Place Locusts at the edge of the ridge in between both zones, closer to Zone B.
6. Spread Hornets and Vultures out between Zone B and Zone C.
7. Spread out any additional Units such as Warthogs, Marauders, and Elites between Zone B and Zone C.

Now that you understand where each kind of Unit should be placed, it's important to know why there are set up this way.

The enemies will often attack Zone B from the west (coming from Zone A) or the north (coming from their spawn point). The artillery Units are extremely useful from the ridge as they usually wipe out most of the AI before they can really become a threat to Zone B. In the event they do make an overly aggressive push from either direction, the vehicular firepower placed at Zone B should keep the enemy at bay quite easily. The Engineers and Nightingales supporting your artillery Units are also key here. Typically, your artillery Units should never succumb to destruction due to the constant healing provided.

Often, the enemies will try moving to Zone C as well. The artillery, as well as the Hornets and Vultures placed along the ridge, will combat the enemy infantry and vehicles moving to Zone C, while the Reavers and Wolverines help combat any Air Units.

It's very important to note that during the match, players need to focus on destroying Energy Pods and collecting their Energy Crates. Energy is the only way you can play your cards. It's recommended to use the more mobile Ground Units (Marauders, Assault Elites, Warthogs, and Reavers) to move around the map and collect Energy on the tailend of each Wave and in between Waves as well. If anything, only one player should focus on collecting Energy while the other player focuses their attention on making sure things run smoothly at Zones B and C.

Overall, there isn't much else to explain about this strategy. To recap, Zone B is heavily guarded by powerful vehicular firepower, Zone C is guarded with just enough firepower to combat enemy forces that slip in, and the ridge in between both Zones is packed with both artillery and Air Units that generally destroy just about anything the enemy tries to throw at you before it even becomes a real threat.

After clearing Wave 25, which won't be that bad using the setup outlined above, the achievement will unlock for both players in the match. If a visual representation of this strategy is preferred, please check out the video below, provided by UntilTammaroYT.