Darth Vader
Darth Vader is tankiest hero in the game and I able to take a lot of damage. He starts with 900 health and this can be increased with star cards but he's not very mobile. There are ways to work around this like using the dodge ability to dash to cover and holding down a position by blocking blaster bolts while waiting for your team to back you up. Blocking is key to winning with vader as it allows you to hold of a whole team of enemies for a short amount of time so use it with dodges to slowly work your way towards the enemy and kill them. His saber throw also really helps with holding enemies back as you can kill them without leaving your position, so you can combine this with your dodge and block to kill enemies while coming out of your block and then dodging to cover. His force choke is useful against heroes because you can get some easy damage on them while your team can get shots at them but be careful using it in galactic assault as even if you choke 3 enemies and there is one left, he can easily be killed due to the choke leaving him vulnerable. His third ability gives him damage boost and resistance so use it before going into a fight and you can use it mid air to cancel some of the animation leaving you less vulnerable. I would also recommend using the star card where a kill gives you health as you can regain a lot of health by staying in cover and killing people with your saber throw.