Militants have unlimited ammo.

only if shooting at the defense units... and not only militants, but all (almost) your army units can do that.

the limit is 2 minutes max though...

You mean that its not a bug? In arsenal info units have ammo limit.

The limits apply once you are destroying the base, not when you're fighting the defence as far as I understand it. That's why sometimes you get so far with a unit and it is carried away. That never seems to happen fighting the defence. You either die or fire your weapon until you reach the base when the limits seem to apply.

But units have not only building damage limit.

true... most lose ammo on the defense (best example: firehawk or vertigo) and have little left to fight the base buildings... others though don't lose any ammo on defense (example: Salamander or Kodiak).

no unit finishes ammo on defense only though for the duration of the attack (max 2 minutes).

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knowing this... u can start to be sneaky and use low level units (level 1s) as distraction so that u can send the high level units on a clearer path:

• send level 1s on one side in the first lines of attack.
  
• send high level ones on the other side starting with the 2nd line of attack.

send only 1 type (2 max - air only usually for NOD or vehicles for GDI) of high level units.

this is most usefull at high levels as u can save a lot of rt if u master the sneaky stuff :wink: