Taken from the revised Dedicated Server Documentation

FRENZY - Free-for-all mode. Equipment loadouts are randomly assigned every 60 seconds (all players receive the same random loadout). Killing a player increases your score multiplier, highest score at the end of the game wins.

POSSESSION - Free-for-all mode. First player killed drops an alien flag, hold the flag to score points. Highest score at the end of the game wins.

TEAM POSSESSION - Team based variant of possession, holding the flag scores points for your team. Highest team score at the end of the game wins.

I don't care about rule unless it has Power Struggle.

Can we control vehicles freely?
Can we go anywhere of map?

There are important points.

Dude, this all sounds pretty cool. Frenzy especially sounds awesome.