idk if you consider this custom or not but i use it a lot so here goes:
Medicham @ choice scarf
Jolly Nature
EV's: 252 atk/252 speed/6 hp
Moveset:
-Hi Jump Kick
-Ice Punch
-Thunderpunch
-Psycho Cut
Description: This thing can wreck in both OU and UU battles alike. Thunderpunch and Ice punch make salamence and gyara think twice about attempting to DD up in your face, as you can ohko both of them if they DD on the switch-in. Hi Jump kick scarftrans, and Psycho cut those pesty brelooms and machamps for the KO. An ohko on machamp is fairly unlikely, but if its at 3/4 hp, you can count on it KOing.
