MYSTERIA
Virtually nothing is known about the woman called Mysteria. The obscure heroine called Vagabond posed as Lisa Winters, the alleged sister of Mysteria, during her infiltration of the infamous Scourge organization in the first USAGENT mini-series, so it can be presumed that Mysteria's last name is Winters, but her first name is unknown.

Mysteria is a petty crook who operates mostly in Las Vegas and uses fog generators to help perpetrate these crimes. She also carries what she calls her "Mist-Sticks", which create an electrical discharge strong enough to paralyze someone's motor functions for a short time.
My first exposure to Mysteria was in Captain America#389, when she participated in a massive attack against both Captain America and Paladin on the S.S. Superia. Her most notable moment happened in Captain America#392 when she teamed up with Arclight (of the Marauders), Bombshell, and the Wrangler to try and subdue Cap.
During this fight, Mysteria used her smoke generators to envelop Cap and obscure his vision so that she could jolt him into unconsciousness with her "Mist-Sticks". However, Captain America knocked Mysteria off-guard by swinging the Wrangler's body into her via the Wrangler's lariat. Mysteria recovered and went after Cap again, but she was taken out for good when Cap swung his arm around and nailed Mysteria with his famous shield. On an interesting note, after Captain America knocked out Mysteria, one of her "Mist-Sticks" hit Bombshell in the leg and caused her to fall over. When Bombshell's hand touched the floor, her powers caused an explosion, knocking her out and taking her out of play.

Mysteria hasn't been seen again since this storyline. She, like Ice Princess, is another interesting character whose potential is just waiting to be tapped.
Mysteria's List of Appearances:

Captain America#389-392
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