Tela Vasir

Tela Vasir is an asari Spectre and powerful biotic known for her investigation of the theft of confidential galactic economic data from the Citadel Council's Ministry of Finance in 2185, and her role in the dissolution of a slave trading ring in the city of Aegohr on the salarian colony of Nasurn. Vasir is later present after Liara T'Soni disappears from her apartment on Illium, where she meets and assists Commander Shepard.

Lair of the Shadow Broker
When Liara T'Soni requests that Commander Shepard meet her at her home on Illium, Shepard arrives to find Liara missing and her home ransacked. Local authorities have established a crime scene and demand that Shepard leave, however Tela Vasir intervenes and allows Shepard to investigate the area, explaining that Liara had fled only moments before.

After Shepard finds a recording of Liara and a contact discussing the Shadow Broker's next move at the Dracon Trade Center, before being spooked by the sound of a break in, Shepard and Vasir head to the Center with Vasir covering the building from the roof down from her hovercar. Shepard and the squad battle their way through the Dracon Trade Center, finally arriving at the office where Liara was meeting her contact. As the squad enters, they find Liara's contact dead and Vasir taking care of a merc, saying she arrived too late to stop the merc from killing the informant.

Vasir asks if they found Liara, Shepard replies that they didn't but then Liara comes out from the shadows, pointing her gun at Vasir. After Liara reveals that Vasir tried to kill her, Shepard and the squad also turn their weapons on the Spectre. Vasir shatters a window to escape, throwing the glass at the squad, but it is repelled by Liara's biotic field. Vasir then tries to escape out the window, but is tackled by Shepard and they fall out the window. After a brief melee fight, Vasir throws off her pursuers and escapes while the squad has to deal with more of the Shadow Broker's mercs.

Shepard and the squad fight back through the Trade Center, pursuing Vasir until they reach the landing pad. There Vasir and Liara are already engaged in a firefight and Vasir, now outnumbered, calls her skycar and jumps into it. Shepard and Liara give chase through the skies of Illium pursuing Vasir. Vasir tries many ways of throwing them off, but ultimately crashes into another skycar, and crashing on the roof of the Azure Hotel. She radios for backup and starts moving away, with the squad in hot pursuit.

After fighting through more of the Shadow Broker's mercs, they finally corner Vasir in a plaza, where she takes a hostage. She engages Shepard in conversation but ultimately the squad and Vasir fight it out. After a protracted battle, Vasir takes one too many hits and crumples near one of the walls. After Liara takes the disk that Vasir had, that they needed to find the Shadow Broker, Vasir engages Shepard in dialogue one last time. Before she dies, Vasir argues that Shepard's partnership with Cerberus is no different, if not worse, than hers with the Shadow Broker.

Capabilities
Offensive

Tela is armed with a Vindicator Battle Rifle and will use Shockwave to dislodge you from cover while inflicting minor damage. She can summon reinforcements consisting of Rocket Drones and Shadow Broker Engineers. If you are too close when she comes out of a Charge, she can also inflict damage and knock Shepard off guard. She also has a powerful pulse attack that causes major damage in a wide radius around her and knocks anyone caught in it off guard, though it has an extensive charge time that allows Shepard to get out of range.

Defensive

Tela's barrier and armor are extraordinarily strong and she will use Charge to move around the battlefield many times.

Tactics
General Tactics
 * Tela is arguably one of the hardest enemies in the game. She will try to keep some distance from you to use her assault rifle. Engaging her at close range is a good idea, since she doesn't have any close range attacks, just watch out for when she Charges. Once significant damage has been done to her barrier, she will exit the area and summon a squad of two Engineers and two Rocket Drones on you. She will do this again once enough damage has been done to her armor. She can knock you out of cover with a Shockwave, and her Charge can stun you, so be careful about engaging at range. Once her armor is down, hit her with a biotic Pull or Liara's Singularity and finish her off; falling off the edge of the battlefield for any reason will instantly kill her, saving the trouble of having to wear down her health.
 * Liara's Stasis is a good ability since it can stun Vasir even if her protection is still up, and turns her into a sitting duck once it wears off. If you use Stasis just before Vasir charges down after a wave, the resulting ragdoll will (usually) fall backwards instead of off the ledge. This causes the next wave to start sooner than normal and, after the final wave, will end the battle without having to bring down her health. This method isn't always possible, due to the line-of-sight requirement to use Stasis. To keep her in sight, try staying in the center of the map below where she charges from after every wave.
 * Tela seems to be more vulnerable to powers during her biotic attack's charge time, so unleash squad powers on her for greater damage. Hitting Vasir with two or more powers will also prevent her from using this Charge attack against Shepard, which could save you some time.
 * Heavy weapons like the Cain will not destroy her outright, it will just lower her barriers.
 * Once her defenses are removed, Tela is susceptible to Dominate and can be kept immobile for the remainder of the fight by using that power.
 * Also, you could use any biotic abilities such as Charge or Shockwave, to knock Vasir off the edge of the map, instantly ending the boss fight.

Class Specific Tactics
 * If you are a Vanguard, a good tactic is to somehow strip her out of her barrier, then equip a shotgun and Incendiary Ammo and pursue her around all the map with your own Charge attack, shooting in her face as soon as you make contact with her. That also makes this encounter a spectacular biotic fight. If you're using a shotgun that is effective against barriers (for example, the Geth Plasma Shotgun), you can use Charge to chase her around the battlefield from the start of the fight.
 * If you are a Soldier, you could come into the fight with a fully-loaded Collector Particle Beam, and the evolved skills Inferno Ammo and Improved Cryo Ammo. You can use the Collector Particle Beam to destroy her barrier. For her armor you can switch to your pistol or sniper rifle with Inferno Ammo armed. Finally, when her health bar is exposed, use the Improved Cryo Ammo with any non-heavy weapon and simply keep firing.