Vido Santiago is a human mercenary and a co-founder, with Zaeed Massani, of the Blue Suns. Zaeed controlled the mercenaries while Vido managed the finances. Arguments ensued when Vido wanted to hire batarian mercenaries, citing the cheap labor opportunities; Zaeed strongly disagreed with this policy. Eventually, Vido betrayed Zaeed by turning their men against him. Vido usurped Zaeed by paying six of his men to hold him down while he shot Zaeed in the head. Vido took control of the Blue Suns, managing their activities from the shadows.
At some point thereafter, Vido ceded de facto leadership of the Blue Suns to Solem Dal'serah, a batarian. This ingenious strategy both strengthened public relations and ensured his own safety. Since, he has gone by the title of "Co-Executive Officer".
In 2185, Vido is contacted by a Dr. Farrin from ExoGeni Corporation to provide safe transport for a Prothean artifact on Joab. Believing the artifact itself to be far more valuable than Farrin's transportation fee, Vido betrays Farrin, directing Captain Narom from the Blue Suns Base on Sanctum to torture Farrin's intermediary until he gave up the location of the dig site. Vido then sends a team to steal the artifact and transport it to the recently hijacked MSV Strontium Mule, but this plan is foiled by Commander Shepard.
Vido also seizes control of a refinery on Zorya, using its workers as slave labor. Shepard and Zaeed are able to track him there. However, the ensuing battle resulted in a fire which endangers the Eldfell-Ashland refinery's civilian workers. Shepard has to make a difficult choice: let the workers die in order to take Vido down for good, or save the workers, potentially giving Vido the chance to escape.
If the refinery workers are saved, then Vido will escape the refinery in a gunship, but will be reminded of his own mortality when a soldier next to him dies from one of Zaeed's shots. If the workers are left to die, then Zaeed will be able to wound Vido, causing him to drop in a pool of flammable liquid. Zaeed then ejects a heat sink into the pool, burning Vido to death.
- Among sequences cut from Mass Effect 3 is a conversation that takes place between Shepard and Zaeed on the Citadel, in which he recalls to Shepard his continued manhunt for Vido if he escaped in Mass Effect 2. Zaeed describes his assault on the Blue Suns' base Vido was hiding in and successfully trapping him, only for the Reapers to attack the colony and a Harvester to take Vido away.