What The Avengers: Infinity War Cast Look Like In The Comics

In the Comics:

Proxima Midnight is Thanos's deadliest and most skilful fighter in his army, wielding a spear forged for her by her master, which bore a sun trapped in distorted space-time.

With the powers of a star, supernova, and black hole all at once, the spear is able to wield great energy, as well as draw it out of others. Proxima Midnight was faithful and loyal to Thanos, and in one of his attacks on Earth was able to bring Namor to his knees and ransom Atlantis for an Infinity Gem.

In the Film:

As one of Thanos's Children, Proxima Midnight, alongside Corvus Glaive, goes to retrieve the Mind Stone, facing off against the renegade Avengers before retreating after Corvus Glaive is mortally wounded.

During the attack on Wakanda, she commands Thanos's armies, able to order multiple drops of hound-like alien creatures to break Wakanda's defenses.

She's killed during a fight with Black Widow, Okoye and Scarlet Witch, thrown into the path of a gigantic death wheel. She's played in partial motion capture by Carrie Coon, and while she resembles her comics counterpart, instead of a helm, her horns are part of her skull, with her eyes set into their base.