We run multiple variations of Counter. The core of the play is down blocks and/or double teams play side, just like Power. This is why I think counter is a must have in your arsenal if you run power, because there is so much carry over between the schemes. In counter, our Backside Guard (BSG) is the kick out man, now rather than skip pull he will take a very tight inside path to kick out the first color that shows, which is usually the play side DE.
This is all the same in every Counter we run. Our variations come from who our 2nd puller is and who secures the back side. Our 2nd puller is also called the "wrapper" because they will wrap inside of the guards kick out block to lead up on the play side LB. If the opposing DE steps down to wrong arm our guard will drive this, logging the DE, and our 2nd puller and Rb have to read this and bounce around it.
Counter FB
We will use the FB as our second puller, this tells the BST to stay home and secure the back side.
Double Tight Counter
This is very similar to counter FB, but we run it from double tight, we use our BS TE as our 2nd puller since we don't have a FB in the game. This was a great play for us, the extra gap in double tight was great for us because it isn't something you see much with so many teams spreading out on Offense. Being in this balanced look up front also helped to stop teams from loading up one side to shut down Power. We could line up the same and call the play either direction. We miss a down block in this clip but it is a great example of our 2nd puller working down the field to spring us for a huge TD.
Super Counter
I didn't run this scheme often but it had serious big play potential because we are aligned in a heavy formation to the strong side, but then pull 3 players to the weak side. In super counter, we have 2 wrappers. We pull both the FB, and the TE up through the hole to lead for the RB.
QB Counter
The last type of counter I want to describe is often called GT. The T represents the BST acting as the 2nd puller and wrapping up to LB. If we ran GT to our RB we would either block the BSDE with the FB, or have to read him. In this example (my favorite play if you have an athletic QB) we use the RB to block back side and have the QB keep the ball. This maximizes our blocking while being spread because we use the back as a blocker, and it provides some misdirection by faking to the back and going the other way.
In most cases if the defense is shutting down power, counter is wide open.