She was one of the members of the Acolytes group loyal to Magneto in Genosha.
She was seen apprehending a mutant criminal trying to escape.
Powers and Abilities
Malleable Bio-Mercury Form: She is composed of a non-toxic liquid mercury. Her form allows her to alter her shape by collapsing into a featureless mass, extending blades from her skin, or molding herself into different forms. Her ability to shape shift extends to the most basic of rudimentary weapons. Her liquid mercury form is non-Organic.
- Self-Sustenance: She is no longer a carbon-based life form and does not eat or breathe the same way as normal humans. Still, she consumes food out of habit and has not realized the scope of her change.
- Telepathic Resistance: She is very hard to telepathically detect or influence while in her mercury form.
- Molecular Adhesion: This gives her the ability to cling to solid surfaces and move her body at will even without overt locomotive features.
- Enhanced Durability: Her skin, bone and muscle transformed into liquid mercury to make it stronger and harder than human; impervious to injury to a certain extent.
- Magical Resistance: Due to her transient body, its harder to magically detect, influence, or harm her them other humans and mutants, but her resistance is far from infinite and can be overwhelmed by more skilled magicians like Belasco and Magik.
Mercury was considered a Significant Threat by the O*N*E, at the time of the M-Day. Nimrod later classified her as a Threat Level: Medium.
Normal human female with moderate regular exercise.
Electricity stuns Mercury and causes her to lose control over her form, as well as causing pain.
- The use of her powers can sometimes be embarrassing for Cessily: with her ability to re-shape any part of her body, she is able to "melt" herself and turn into a living puddle of mercury. When she does this, however, she is unable to keep her clothes on. Therefore, when she shapes herself back into her humanoid form, she will be nude.
- Cessily's is disappointed about not losing her powers due to M-Day, as she was seen looking into a mirror and while saying: Why not me? Why not me?.
- Her creators stated that she is Irish-American. In her first appearance, she was sixteen-years-old.
- A previous male character with the same name and similar powers was introduced as a part of Cerebro's X-Men.
- It has also been said by her creators that she can potentially do anything the T-1000 (Terminator 2) can.