Dion is a new character introduced in Metal Slug Attack, making his debut in the Extra Ops "Hot Trap".
Originally one of Abigail's spies, he was promoted to Lieutenant after she was impressed with his combat capabilities. He serves as her right-hand man and is a skilled fencer, using an rapier to attack his enemies. He also carries a pistol for ranged combat. Much of his personal information is secret, as Abigail doesn't even know his actual name.
Dion is ACE's second-in-command, which is an elite fighting squad that serves Abigail.
During a meeting in the past, when the Professor failed to show up, Dion asked Abigail if he should forcefully bring him due to his constant absences. Abigail tells him not to, though she states that it would be nice if he could send someone in his place.
Dion later "allows" Caroline to escape with the Sky Jupiter Queen and causes a panic at the prison, especially with Izabella who had started to take a liking to Caroline. Dion does not state why he allowed her to escape, though it is presumed that he was trying to find the Ptolemaic base.
First appearing in "Subjugation Tactics", Abigail discreetly contacts him to begin her plan to kill the Professor. Beatriz, having heard rumors from Vicky that Dion might be trying to take Abigail's position, asks him what he is doing. He flatly states that he knows nothing and leaves to rendezvous with Abigail.
After taking out the initial sentries, Dion sets jamming devices per Abigail's orders to prevent the Martians from using telepathy. As Abigail carries out her part of the plan, Dion confronts Marty, who had set out to destroy them. Dion successfully stalls Marty long enough for Abigail to kill the Professor.
- He bears a certain resemblance to a portly John Crawley from SNK's Art of Fighting series of fighting games And Raidou Kuzunoha the XIV from the Devil Summoner series.
- He is the third male character to wear sunglasses since Clark Still and Tarma Roving.
- Like the Aikawa sisters, Hyakutaro Ichimonji, and Sisilia, he runs away upon being defeated.