what are the best anti light/heavy-tank units (nato and pakt)?

cost efficient would be all the ATGM platforms (like jeeps with mounted ATGM)

This is a question with no answer. Why?

It all depends on the position. The correct answer may be gunships, ATGM infantry or vehicles, other tanks or infantry with bazookas. Maybe even artillery. It's easier to list the units that are not strong against tanks, given the right circumstances.

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Wargame: Disco Edition

http://i.imgur.com/KwSCdxW.png

Helicopters with Rocket Pods work well - they route heavy tanks, and others shoot it in the back. But that works only if enemy AA can't cover tanks.

Vs light armor, you need either lighter units that are much cheaper (like BTR 70 or AML 90) or something that has higher armor than the one enemy tanks can penetrate (but you need to be far away, on point-blank even AP 1 cannons can penetrate just about anything).

Flamethrowers route any tanks in seconds, so if you can get in range to heavy tanks with them it routes anything and you kill it in back armor. Works against big swarms of light tanks just as well.

If you can't route heavy armor and can't zerg them with light-tanks/infantry on point-blank range, missiles are probably most efficient (infantry or vehicles). But you need at least one truck so to resupply missiles. However, if enemy repairs heavy armor with trucks missiles kinda suck too.

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Knowlege is Power!

True on the last part, however you still inflict morale damage. That was a huge thing about 3 Mile Island in beta that me and my friends learned. You may not be able to kill the tanks, but lots of spread out ATGM missile infantry firing on tanks will panick him and force him to run away. Those long range fights become more about detering the enemy than outright kills, forcing him to burn through more supplies and time than you do.

Also, routing tanks often expose back armor, and then your ATGM infantry will have kills.

Whilst it is pretty situational, I've had some success with the following AT units.

Wiesel TOW's
Oh sure, the Jeep TOW is cheaper and has better fuel economy, but the Wiesel has armour, so when it messes up and get's a pair of Hinds on it's tail it can sometimes survive long enough to get to the safety of your Stinger Troops or Flaktanks.

Marder VTS
20 points, decent operational range, reasonble AT gun, reasonble armour (for a vehicle). Just remember: NO STABILISER. Just treat it as a supplement to your MBT's (or Cav Tanks if they're your thing, it's pretty fast) or hide it in trees.

Opinions largely, but with NATO you're looking for relatively cheap options to supplement your more expensive tanks.

Vet ATGM infantry. I just had one vet 5 ATGM kill 2 abrams tanks in two salvos, which is amazing cost efficiency.

Remember that in general your army composition should be inexpensive infantry and tanks up front with your more expensive and accurate units behind. The PACT forces have infantry that cost $10 so for $40 you have 4 units that take quite some time to kill by regular enemy units (4 carriers and 4 inf units). This lets your ATGMs have enough time to fire off about 3-4 salvos, which should net you a substantial number of vehicle kills.

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