Targeting Macro

I was in a group doing Copperbell and i saw what i assume was a macro in use by the tank. When we approached a group of mobs, the targeting markers (1, 2, etc.) suddenly popped up on the mobs. I assume it\\'s something like picking a target and when you hit the macro it assigns the 1 marker, selects next enemy and assigns the 2 marker...

I am a poor macro-maker so I\\'m hoping someone can tell me how to set this one up for when I startup my marauder. It's a good tactic to indicate to the DPSers which mob to focus on first.

Don't need a macro for that. He could've just had the marking on the hot bar and click it as he cycles through target. I know I leave my 123 marking on the 5th cross-bar to tank on controller.

Did not think of that. It did happen instantly, which is why i thought macro instead of his cycling thru the mobs. Thanks.

CAN a macro be set up to do it with one button though?

I don't think there's a macro action for cycling target that you can target 1, mark it, cycle through, mark target 2 or something but a tank can set up an action macro to say use tomahawk, mark target 1 though you should've marked it before the fight.