Halo Wars Demo

The Halo Wars Demo is the pre-released version of Halo Wars. It was released on February 5th, 2009.

Campaign
The demo contains two campaign levels, Alpha Base and Relic Approach. In the first level, playing as Sergeant Forge, the player is tasked to help the marines to fight against the Covenant. Eventually, you will receive a convoy of Warthogs and move into the base. You then fight the remains of the Covenant and take it back.

In Relic Approach, the player starts the level by by fixing up the base, building a Barracks and Supply Pads to train Marines. The player then follows Sergeant Forge to the Relic, killing Covenant forces along the way. Reaching the Relic, the Covenant inside it must be killed and a detonator intended to destroy the relic must be taken out. A cutscene starts when you finished the level. In the cutscene, Sergeant Forge and Anders with Marines escorting them venture into the Relic, only to be ambushed by Stealth Elites. The level ends with Forge requesting for backup from the Spirit of Fire.

The Campaign only features Easy, Normal and Heroic difficulties. (Legendary is not included in the demo.)

Skirmish
In Skirmish mode, you can only play against an AI on Chasm. The only hero units players can choose are Captain Cutter and Prophet of Regret. As with Campaign, the A.I. difficulties that can be chosen are Easy, Normal and Heroic.

Mistakes

 * The Magnetic Accelerator Cannon is called a "Mass Accelerator Cannon."
 * SPARTANs have two health bars, one of which is a shield. The Mark IV armor did not have shields.
 * HEVs can fit entire ODST squads in them.
 * SPARTANs can have Neural Implants. The Mark IV armor could not support an AI.
 * SPARTANs can also wield Machine Gun Turrets, which could not be picked up by the Mark V armor. A possible explanation is that Halo: Combat Evolved did not have Machine Gun Turrets.
 * Spartan Lasers are used, but, considering how the UNSC had no intel on laser weaponry during the start of the war, it seems impossible that the lasers would exist.
 * SPARTANs can also wield two SMGs at one time. The Mark V armor did not have the ability to track two weapons at a time, so it is unknown how the older Mark IV can do it.

Trivia

 * At the main menu it gives you tips and trivia for Halo Wars.
 * The main menu screen shows the first Halo Wars trailer in the background.
 * The menu is very similar to the Halo 3 menu.
 * The demo has been downloaded over 2 million times in the week following its debut, setting a "day one record" in its initial release.