Troperion's Rocket Punch divides in mid-flight into dozens of little hands that trickle the opponent into submission before reassembling into a fly-swatter like contraption that pounds it into the ground before reassembling to give it the finger.
Troperion's arm is broken off, and he throws it at his opponent with his other arm. (see: Dai-Guard, Shin Mazinger)
Zig Zagged: Out of weapons, our hero tries to use the maneuver against Monster of the Week, which stops the punch effortlessly. "He he he... He just fell for it". Cue the click of a trigger and a gigantic explosion produced by the bomb hidden inside Troperion's arm. But it turns out the monster is still not dead! "Damn it! Not even that was enough... However, I still have one last chance." So our hero fires the second arm, but the monster dodges it. The monster tackles Troperion and prepares to destroy it, but then the arm returns and explodes, hitting both combatantswith full force.
Averted: Troperion didn't have a Rocket Punch.
Enforced: "During the first few episodes, Troperion didn't have a Rocket Punch, but with the advent of the action figures, we had to add it for the sake of 'accuracy'."
It turns out Troperion is just a test-bed for the development of more efficient and conventional super-weapons, with the Rocket-Punch system being the prototype for a new class of impact-missile capable of being used multiple times.
The fist projectile and all the electronics within are extremely expensive to replace, so Troperion's pilot burns through truckloads of money with every launch. Any amount of overuse would result in bankruptcy, so the weapon is restricted to emergency use.
...However, the weapon proves to be extremely effective under the control of its Hot Blooded test pilot, so they decide to deploy Troperion as a full time unit.
Turns out that rocket punches are a lot more useful if you use a cord to retrieve them after every launch...