Stalker – The twist that is unique to the Stalker, with the exception of the Manager and Landmine, is that, while not moving or firing, the Stalker becomes invisible. While difficult to master, it is potentially one of the strongest classes in the game.
Patience: The invisibility from this class is going to be the strongest aspect of the tank. Sitting still and waiting for opponents to come to you proves very easy. Wait for them to sit still or get close, and throw off your cover with a few well-placed rounds.
Lure them in: Sometimes it's best to fire a few shot so you can get the enemy attention. And they might get into your trap without notice.
Letting enemies get too close: Chances are, they may fire and hit your tank, which will blow your cover.
Auto fire: No. It will reveal where you are and grab their attention.
Pretend you didn't see them: If you saw a stalker go invisible, pretend not to see them. Then, suddenly fire at them when the time is right and surprise them. They will not expect someone to know where they are before they come out of cover!
High penetration tanks: When a Stalker surprises you, just try to avoid its bullets and fire at it. Since it is pretty weak when visible, it should be the right time to beat it.
Spray your shot/traps: The best way is to spray your bullet or traps. It will reveal the Stalker position when your bullet hit (ghost-tank effect) or your trap bounce back
Low penetration tanks: Don't attack a stalker with a low penetration tank, for example the Gunner. Its bullets will destroy all your bullets and then hit you.
The landmine: Here, the Stalker will act exactly like a landmine. The build is:7/7/7/0/6/6/0/0. Anyone touching the Stalker, which is invisible, will die due to the Body Damage.
Balanced: The build goes as 2/4/4/2/7/7/7/0. This is useful if you want to snipe, but expect some rammers and need more health. Beware of long shots, however as your bullets move quite slowly.
Normal build: 5/7/0/7/7/7/0/0. You don't have to move a lot thus your main advantage is to become invisible, so try to exploit that. Upgrade health more in case you set your ambush in a place where lots of people spam their bullets.
another good build:0/7/0/7/7/7/5/0
Before the August 11th update, the Stalker could be seen very faintly when 'invisible'. You just had to look VERY closely to find them.
The Stalker turns invisible after 1.5 seconds when stationary.