Dexter Vex was a member of the Dead Men. He was present at The Corpse Attack in Denmark and at Anton Shudder's birthday. After the War ended, he decided to start travelling the world. He is said to be "living the life of an adventurer."
Sometime during the 1800s, Vex met Gracious O'Callahan and Donegan Bane whilst tracking a vampire in Hong Kong. After the incident, they remained firm friends ever since.
In 1861 he chases Serpine along with the Dead men in the wild west.
In the late 1960s during the Vietnam War, Vex met a girl named Sally in San Francisco and became a hippy for a couple of years. He went to peace marches, grew his hair long and became a vegetarian. However, when he and Sally went to the airport to pick up her friend from New York, they passed a GI returning from the Vietnam War. Sally spat at the soldier and called him a baby-killer. Vex, feeling that although he didn't agree with what the Americans were doing, still respected the warrior, so he cut his hair and gave up the life of a hippy. Two days later, he was tracking the head of a death cult in Congo.
Dexter also claims to have taught Skulduggery how to dance, while he and Valkyrie are admiring Skulduggery's dancing skills "I taught him everything he knows of course. Before he came to me he had all the co-ordination of a turnip. I turned him into the dancer you see before you."
Vex is briefly seen fighting for the Resistance, led by China Sorrows. He breaks Valkyrie out of prison after she is captured by Mevolent. Later on at the battle of Rathoath, his arm is chopped off by a Redhood. He is now presumed dead.
Vex leads a group of Sanctuary agents to find the God-Killers and secure them. Tanith Low is also leading a team to secure the god-killers and burn them so no one can kill Darquesse. His team ends up obtaining the fakes Tanith had left, and didn't succeed in stealing the God-Killer Sword from the English Sanctuary.
Along with the rest of the Dead Men and their new-found member Valkyrie, Dexter fights on the Irish side in the war between Sanctuaries. He takes part in the mission to retrieve The Engineer in the French sanctuary. He also fights in the battle against the Warlocks, and is later assigned to capture the supercharged mages when the battle was over.
Vex goes around the world, tracking down the renegades along with the Monster Hunters, Fletcher, Saracen and Dai Maybury. He helps to defeat and capture a Remnant while it was possessing a man called Noonan. He is taken over by a Remnant halfway through the book, and attacks Valkyrie and her family. He holds Alice hostage and makes Valkyrie and her parents chase after him and draws them into a trap. He then forces them to take their car and drive him to Roarhaven. They are stopped just outside the gates, and then are attacked by Samuel and Vincent Foe. Valkyrie figures out how to use her lighting powers and kills both Foe and Samuel. Vex flees after a scuffle at the Roarhaven entrance. He later takes part in the final battle against Darquesse, and sends all of the Remnants to throw themselves down Darquesse's throat and possess her. She kills all of the Remnants once they get inside her, then grabs Vex and forcefully pulls the Remnant out from inside him. This results in him being grievously injured and losing a lot of blood. He is tossed away by Darquesse, and a watching Valkyrie is unsure if he is dead or not. He is not seen again.
Dexter Vex, confirmed to be alive, is referenced several times in Resurrection. During a conversation between China Sorrows and Valkyrie Cain it is mentioned that Dexter is not "on good terms" with Saracen Rue.
Magic and Skills
Dexter Vex is an extremely powerful mage, who chose energy throwing as his chosen discipline. He seems to be extremely capable in this, keeping the horde of rage-zombies at bay for some time.
Vex is also a skilled street fighter, able to take down the vampireDusk without using magic, despite being recently shot in the leg, with Dusk was using a rifle. During the war between Sanctuaries Vex used a gun, sword and armoured clothes made by Ghastly Bespoke.
When Derek Landy was asked about his sexuality, he responded that there was none when one was 400 years old.