From the patch notes...

The Engineer!

We are happy to introduce WildStar’s Engineer! It comes fully loaded with rudimentary gadgets and bots made from the best junkyard metals.

* Available Roles: DPS or Tank

* Armor Proficiency: Heavy

* Weapon: Heavy Gun

* Optimal Range: Mid to Long Range

* Resource: Volatility

Generated while in combat by abilities such as Pulse Blast and consumed by powerful abilities such as Electrocute. Starts empty and dissipates out of combat.

Has a default max value of 100

* Innate Ability/Stance: Eradication Mode (DPS)

* Passive: Increases Assault Power but reduces Damage Mitigation

* Active: Enter offensive Mech Suit mode

* Innate Ability/Stance: Provocation Mode (Tank)

* Passive: Increases Threat Generation

* Active: Enter a defensive Mech Suit mode

The Medic!

… and in this corner, we have the Medic! They come equipped with the most advanced technology of all the classes.

* Available Roles: DPS or Healer

* Armor Proficiency: Medium

* Weapon: Dual Resonators

* Optimal Range: Mid to Short Range

* Resource: Power Cores

Consumed by powerful abilities such as Gamma Rays and generated by abilities such as Discharge. Start full and regenerates while out of combat.

Has a default max value of 4

* Innate Ability: Energize