This is a guide to the map Fort Knox. Fort Knox is a medium sized map that allows up to 7 players per team. It features all the modes. For easier understanding, I will be using the red team as my perspective for team based modes. (Unable to find a birds eye view of the map so I just used one with gold box locations, source: http://en.tankiforum.com/index.php?showtopic=234421; if you are able to find a better image, please pm me.)
Deathmatch
For Deathmatch, I would highly recommend camping, or taking control a corner or edge of the map. This map has plenty of obstacles to hid behind. Mounting a medium range weapon, you will be able to pick off enemies quickly. Heavy medium hulls are both viable as you often spawn at locations with lots of cover.
Team Deathmatch
When you play Team Deathmatch, generally you should take control of your side, this would be the east side. Make sure to eliminate any enemies that pass the vertical wall.
Up north, generally you want a medium ranged combinations to close off that choke point; weapons include Twins, Smoky, Vulcan (generally infinite ammo and is able to confront short range turrets); this position should be covered with a heavy hull.
In the south-east section, you would want two or more Isidas to cover the middle gap as well as heal teammates. Medium hulls provide the hp and mobility for this role.
In order to make pushes, you would want medium to long range weapons along the southern ramp in order to make pushes into the middle. If your team is able to take control of the center area, they you should have Railguns, Shafts, Thunders or Magnums on the high grounds of your side.
Capture the Flag
You would want to take control the map as well. Everything to help defend is covered in Team Deathmatch Section.
Due to the amount of cover in this map, flag pushes only require close and medium range weapons. Strong pushes include Hammer, Smoky, Thunder, Ricochet and Viking; Isida and Viking for healing; and a few tanks for cover, such as Firebird, Freeze or high knock back turrets on a suicidal mission to help the flag carrier out.
For defending the flag, you want your two or more Isidas; a Freeze and Hunter; and your good old Vulcan, Twins or Smoky/Mammoth to sit on the flag.
Control Points
Similar to Team Deathmatch you want to continuously make pushes in order to gain more points. I would suggest that you place a heavy hull with a Vulcan on points that you have already captured.
Additional tips
Isidas are very powerful on this map due to the surplus of cover.
The multiple small choke points (ramps and wholes in the wall) allow for great mine placement.
Magnum is really effective due to the multiple height differences.
Ricochet, hammer and thunder are effective by being able to hit hidden enemies.
Ramming enemies at ramps is useful for flipping them.
Great Combos
Isida and Viking - Healer
Vulcan and Titian - For zoning
Smoky and Mammoth - Blocking/Flag camping
Hammer and Viking - Flag carrier
Freeze and Hunter - Flag defense
Thunder/Smoky/Railgun/Ricochet and Hunter/Viking/Dictator - Midfield
Magnum and Hunter/Viking/Dictator - Support