@wildvine: The counterpart thing is down to real life bug summo events, with stag beetles (Pinsir) and Rhinocerus Beetles (Heracross) being the strongest and most sought out fighters.
It extends to Digemon too, since Karbuterimon (Rhinocerus Beetle) and Kawagamon (Stag Beetle) are the good/evil counterparts of each other
Scizor is another of the '40 missing Pokemon' but it's evolution and typing made it hard to code.
@avenging_x_bolt: They were originally counterparts in the original 190 Pokemon but Game Freak ran out of time to code Heracross into Red, Green/Blue and Yellow.
That said trade a Missingo to Gold/Silver/Crystal and it'll turn into one of the 'missing' 40 Pokemon
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