Mayhem Brawler

This is easily obtainable on Level 7, the path where you fight zombies.

The zombies are easy to control. Stay a full screen away and mash your attack button to combo them, back up and wait for the fist above their heads to disappear, and then continue your attack. Don't try to grab them, grabbing is so slow it often means you take a hit. Use the Y button for your special attack or your dash attack if you are about to be surrounded to easily escape the pressure and go back to safely attacking them.

For the ghouls'n'ghasts, you can easily take them out with basic combos, just be sure to hit the Y button for your special attack if they start running at you. You can safely stand over a ghoul after knocking them down and continue mashing your basic combo.

Once you see the Banshees, you know you are at the end. There are only two of them so just out of their way to avoid their scream attacks, combo them, wait for the fist above their heads to vanish, and then continue attacking. Don't bother trying to throw them, it's basically an automatically counter if you do.

Once you defeat the Banshees, you move onto the next part of the stage and the achievement will unlock. If you mess up at any time, just pause and hit retry.

This can be done on the first stage. I recommend putting the game on the easy setting. Get trough the start of the level until the 2 guards with the guns (right before you enter the section were you fight Chainado) and the achievement will pop.