One thing about Tassadar's special victory condition: if you take an enemy controlled area instead of grabbing an empty area; that's a two-point swing.
Because instead of merely gaining an area, you've made the enemy lose one as well.
Meaning if you have one more area than your opponent and you empty out one of your areas to take one enemy area, you still come out one area ahead. And if instead, you didn't leave any of your areas empty, then you now come out two areas ahead.
So for the new players out there: it's important to remember that as Tassadar, you don't have to control more than half of the total areas in a 2-player game. You merely need to control more than your opponent. (which means, if he doesn't have a unit or base there, then that's one more area-count that you don't have to overtake)
This re-post might be useful.