In Team Fortress: Invasion, the goal is to collect the most resources you can. Resources can be gained by killing enemies, destroying enemy equipment, or collecting resources from a Resource Pump.
Instead of rounds, each conflict is called an Act. Act time limits are set by the mapper.
Weapons are more accurate when crouching.
You can build Vehicles at Vehicle Bays.
The classes of Team Fortress 2 Invasion are somewhat similar, but still different from their original counterparts from TFC and present day TF2.
Armed with a shield and a laser rifle, the Commando is a good class for support against the enemy team. This class is pretty quick. This class is only able to build a Powerpack, and a wagon if you're on the Alien team. Can kick enemies to the ground when close to them.
Armed with a Minigun, this is a slow and heavy class that is good to provide defense against the enemy team by building various defensive structures and by fending them off with the Minigun. This class can build a Powerpack, Bunker, Barbed wire, Dragon's teeth (?), Sentry Gun, and a Manned Missle Launcher. This class is recommended for those that want bullets to fly.
The Escort's main purpose is to protect surrounding teammates using a large shield he controls, which has two different tracking methods. This class can build a Bunker, Sandbag bunker, and a Manned Missle Launcher.
Armed with a burst rifle and his trusty Repair Gun, the Medic can heal teammates and repair damaged team buildings. The Medic can build a Sandbag Bunker, Resupply Station, Buff Station, and the Powerpack.
The Pyro's main purpose may be to burn enemies and destroy enemy equipment, The Pyro can pour gas and light it later, which can be very useful for setting traps. The Pyro is armed with a Gas Can, Flamethrower, Grenade Launcher, and a pistol.
Armed with a Shotgun, Rallyflag Placer, and a Rocket Launcher, the Sapper specializes in both offense and defense. The Sapper can construct a Resource Pump to increase their team's Resource Bank. Can build a Sandbag Bunker, Powerpack, Manned Plasma Gun, Resource Pump, and Dragon's Teeth. The Sapper is the engineer of Team Fortress 2: Invasion.
Armed with his Sniper Rifle and Limpit Mines, the Sniper is a good class to use to quickly and effectively take out enemy players. When standing still for a period of time, the Sniper can become completely invisible, but only when your team had enough resources. Cannot build anything.
A fast, unarmed class. The Recon is good for scouting out enemy players and resources, and also can track enemies that are within a certain radius from the Recon and shows them on the map. This class may have a mechanical, metal glove to be used to punch enemies, each punch charges a stronger electric punch. This class currently does not work and crashes the game. May be fixed for next update.
Very broken, meant to be the Demoman of Team Fortress 2: Invasion. Or possibly just meant for testing.
This class is not a man, but is a robot disguised as a spy. Can disguise as an enemy player, silently kill players, consume corpses if your team has enough resources, and had thermal vision. Good for getting resources without anybody noticing. Can't build anything.
The Powerpack can supply up to 3 nearby objects with energy until it's destroyed. Good for keeping your buildings protected while away.
Able to find and quickly eliminate enemies by shooting high-speed plasma projectiles. Good for keeping enemies out of your team's base.
This object can heal up to 4 players connected to it. A connected is indicated by a wire or tube attached to the player from the Buff Station. If the player moves out of radius, the connection to the Buff Station is lost. Good for players that need healing while the medic is off doing something else.
Although the name doesn't sound as cool, the Barbed Wire is good for keeping out enemies from places you don't need them in. When two barbed wire are placed close to each other, it generates a deadly laser in between them.
Good for keeping cover from enemy fire and also good for protecting vehicles and infantry against enemy projectiles.
Although not as strong as the Bunker, this is good for keeping cover while still attacking enemies, and provides good cover from enemy projectiles.
good for getting places quickly, but isn't very powerful. Recommended use is for transportation only.
If you wanna get places and kill enemies at the same time, this vehicle is for you. Pretty strong against enemy corpses and bodies.
Slow, but good for defending your team's base from oncoming enemies. Shoots missles at a slow fire rate.
Not much of a vehicle, but can be built at Vehicle Bays like all the others. good for trying to get your teammates somewhere quickly, if you're willing to take the risk of placing them to said place.
Similar to the Tripods from War of the Worlds, these are tall, lengthy vehicles that move slow but are good for trying to kill enemies, as it provides cover and transportation at the same time. Alien team only
Just like the Strider, but smaller in size. Uses up less resources, and is pretty good if you have enough to build it, but if you have enough to build a normal Strider, the normal Strider is recommended. Also only for the Alien team.
TF: Invasion just started development, but will see a release very soon. We are currently testing the 2013 port to get an idea of how the game works.