In order to unlock this achievement, the first thing you need to do is load up a Klassic Tower.
This can be found under ONE PLAYER --> TOWERS --> TRADITIONAL TOWERS
Once there select the KLASSIC TOWER and choose LEATHERFACE as your fighter. You then need to pick the KILLER variation. This gives you access to the BERSERKER STANCE.
YOU MAY CHOOSE WHATEVER DIFFICULTY YOU LIKE AND ARE COMFORTABLE WITH
To perform the BERSERKER STANCE, you need to input DOWN, BACK, 3 (A). Once this is done, LEATHERFACE will pull out his chainsaw and take a special stance. Once in this stance you have four options.
PRESS A (Again) - To Exit the Stance
PRESS X - Psycho Rush (A quick sprint into the opponent with the chainsaw)
PRESS Y - No Escape (A series of large swings with the chainsaw)
PRESS B - Running Frenzy (A running move while swinging the chainsaw overhead)
In order to unlock this achievement you need to perform all four of these moves in a single match (again, while in the KLASSIC TOWER).
Note: Each of these moves can be ENHANCED, but it is not needed to complete the achievement.
After performing each of the moves, the achievement should pop. Pretty easy.