The Dark Eldar Razorwing Fighter is a nimble aircraft that can cause havoc if allowed to attack freely. Monoscythe Missiles and Splinter Cannon will make short work of infantry, and its Dark Lances are effective against even heavy armour.
An Imperial Knight Paladin excels in engagements, where its Chainsword and Shock Lance will make short work of most targets. It is also armed with a Battlecannon for long range support.
The Ordinatus Mars is a gigantic mobile weapon platform employed by the Adeptus Mechanicus. Its Sonic Disruption Cannon has huge range, and will destroy absolutely anything under multiple blast templates. It has Void Shields for protection, but will almost certainly be a priority target for the enemy.
Squat Warriors are good all-round troops with more staying power than the average human soldier. They come with missle launchers as standard, providing some long-range support.
On the rare occasion a Squat lives beyond his normal lifespan of 300 years, he develops psychic abilities that enable him to provide expert insights to his commanders.
The Imperial Guard Valkyrie is a transport aircraft with excellent all-round ability. Its Multi Laser and Heavy Bolter provide anti-infantry and anti-tank capability, and Rocket Pods are one-shot weapons that cause considerable disruption to enemy lines.
A Questor Titan is well equipped to take down large numbers of enemy units with each volley it fires. Its Castigator Cannons are especially good at cutting through swathes of infantry.
Plaguebearers are disgusting lesser Daemons of Nurgle that are incredibly tough and formidable in close combat.