Original Skullbuster

The cyborg Skullbuster was a member of the original Reavers, a gang of cyborgs living in a ghost town in Australia, who perpetrated robberies across the globe. Skullbuster, as well as Pretty Boy and Bonebreaker, escape after their defeat by the X-Men.^[1] Under the leadership of Donald Pierce, the remaining Reavers train to defeat the X-Men. The Reavers ambush Wolverine, beat him half to death, and crucify him.^[2] After Wolverine escapes, the Reavers attack Muir Island, where Skullbuster is shot and seemingly killed by Forge.^[3] Skullbuster is not seen again for several years and Pierce recruits Cylla Markham as the new Skullbuster.^[4] When Lady Deathstrike kidnaps Milo Thurman, the mutant mercenary Domino tracks them down and battles Deathstrike, Pierce, and Skullbuster.^[5] Pierce reveals that he resurrected Skullbuster by copying his cybernetic mainframe. However, when the Reavers and the Shadow King battle the X-treme X-Men, a new Skullbuster is present and there is no mention of the original.^[6]

Cylla Markham Skullbuster

Cylla, a pilot, is hired by Banshee and Forge to aid in finding their missing teammates, but they get a lead on Dazzler being in Hollywood so tell her they won't need the flight. She doesn't mind as long as she's still going to be paid, and takes off, but the plane is shot down by Fenris as Banshee and Forge look on; the airfield is then obliterated by Fenris too, and the two X-Men disappear, pretending to have been killed in the explosion and believing Cylla to have died. However, critically injured, Cylla is rushed to a hospital. Donald Pierce visits her, noting she'll never walk or fly again, and offering to make her a cyborg in exchange for taking down Wolverine; in light of having suffered the loss of a leg, the other being in poor condition, and having suffered 40% burns (in Wolverine #55, she claims to have been "less than a vegetable with pain receptors", although she is clearly fully conscious when interacting with Pierce at the hospital, and throughout the cyborgization process), she agrees. After extensive modification, she joins Pierce's Reavers.^[4] Though she is replacing the original Skullbuster, Cylla mainly goes by her real name. After the apparent deaths of the other Reavers, Cylla and Lady Deathstrike flee.^[7] She follows through on her mission to try and kill Wolverine (commenting " I don't need to owe Pierce to take you out, Wolverine - I'd do it just to know I'm alive!"),^[8] but she is defeated through the combined efforts of Jubilee and Yukio.^[9] With Pierce gone, Cylla is unable to have the damages inflicted by Jubilee and Yukio repaired, and so allies herself with Bloodscream against Wolverine. However, Bloodscream betrays her and appears to suck the remaining life from her.^[10]

A female Skullbuster, with the usual skull mask but a seemingly bionic lower jaw/ face covering, and black braids or wires for hair, participated in Shadow King's failed attack on the X-treme X-Men, and after being defeated was handed over to the police.^[6] A female Reaver identified as "Skullbuster"- with brown hair but a similar skull-visor to Cylla's- appeared in Cable and X-Force#15-17 (2013); this is presumably a different individual from Cylla given her apparent unfamiliarity with mutant teams, questioning Cable making "his brat [Hope Summers] do all the heavy lifting" and being told that's how "muties" do it.

Cylla- looking exactly the same as prior to her apparent death at the hands of Bloodscream- reappears with the Reavers in the 2018 Hunt for Wolverine one-shot, having taken a high-paying mission from an anonymous individual to recover Wolverine's remains from his burial site. Whilst the other Reavers fight, Pierce and Cylla- now equipped with a molecular rearranger- work on opening the Adamantium casing within which they expect to find Wolverine's remains. The process taking quite some time, they are bewildered to find it empty; Kitty Pryde (Shadowcat) had previously removed Logan from the casing and buried him elsewhere.^[11]

Operating as an independent mercenary, Cylla is hired by Hawthorne Ryan, a tech billionaire, and faces off against the young novice hero Escapade (Shela Sexton), who breaches Ryan's base in search of an artefact. Although she successfully badly injures Escapade, Cylla is defeated by her opponent's power of "switching circumstances", meaning she ends up with all the damage she herself had inflicted.^[12]