Instructions
Enter the Cianwood Gym, training grounds for Pokemon collectors to test their mettle. Immediately upon entering, look for the gym leader, Chuck, who is too distracted by a waterfall feature to fight.
Follow Chuck's directions to the left and approach the waterfall feature. Two "black belt" accomplices will battle you separately along this path; the highest level Pokemon you will face during these battles is a level 27 Hitmonlee. Neither trainer presents much trouble.
Walk across the room to the right of Chuck and ascend the stairs leading two the third and fourth blackbelts. The third acolyte uses a strong Hitmonchan with fearsome "elemental punches." These present a problem if you only have Pokemon that are suited to "Fighting" element Pokemon. The last trainer has three Pokemon, but none of them are above level 25.
Descend the stairs leading to behind the waterfall and turn off the feature using the switch.
Speak with Chuck and dispatch his Primeape and Poliwrath in a fight to earn "TM01," the Dynamic Punch. His Poliwrath is a level 31 and frequently tries to use a punching attack which takes two turns to charge, but which deals hefty damage and can confuse your Pokemon.