I'd actually just made it to 60 (yay beat Palmer round 2!) with the following...
LEAD:
Infernape (speed boosting nature, EVs to Attack and Speed)
Life Orb; Close Combat, Flare Blitz, Earthquake, Thunderpunch
Close Combat and Flare Blitz carry a base of 180 (after STAB) and with Life Orb can one shot a lot of targets even without hitting weakness. Earthquake covers more weaknesses and Thunderpunch handles pesky Gyarados and Mantine. Recoil damage actually benefits its Blaze ability, allowing Infernape to get in one last superpowered Fire attack.
#2:
Gengar (Timid or other speed boosting nature)
Focus Sash; Shadow Ball, Thunderbolt, Energy Ball, Destiny Bond
Shadow Ball for STAB, Thunderbolt and Energy Ball for hitting more weaknesses. Focus Sash causes survival for killing blows, allowing one to finish off a current target and using Destiny Bond on the next. I've actually clean sweeped with Gengar sometimes when Infernape fails to OHKO a target, and get blasted himself.
#3:
Garchomp (Jolly)
Choice Band; Outrage, Earthquake, Crunch, Stone Edge
Outrage carries a massive 180 power and Earthquake 150 (after STAB), which with Choice Band creates huge problems for what is most likely the last of the opponent's Pokemon. Stone Edge allows for some extra weakness coverage, but Crunch is probably not that useful as even with weakness it only carries 160 power, as opposed to Outrage's 180.
LEAD:
Infernape (speed boosting nature, EVs to Attack and Speed)
Life Orb; Close Combat, Flare Blitz, Earthquake, Thunderpunch
Close Combat and Flare Blitz carry a base of 180 (after STAB) and with Life Orb can one shot a lot of targets even without hitting weakness. Earthquake covers more weaknesses and Thunderpunch handles pesky Gyarados and Mantine. Recoil damage actually benefits its Blaze ability, allowing Infernape to get in one last superpowered Fire attack.
#2:
Gengar (Timid or other speed boosting nature)
Focus Sash; Shadow Ball, Thunderbolt, Energy Ball, Destiny Bond
Shadow Ball for STAB, Thunderbolt and Energy Ball for hitting more weaknesses. Focus Sash causes survival for killing blows, allowing one to finish off a current target and using Destiny Bond on the next. I've actually clean sweeped with Gengar sometimes when Infernape fails to OHKO a target, and get blasted himself.
#3:
Garchomp (Jolly)
Choice Band; Outrage, Earthquake, Crunch, Stone Edge
Outrage carries a massive 180 power and Earthquake 150 (after STAB), which with Choice Band creates huge problems for what is most likely the last of the opponent's Pokemon. Stone Edge allows for some extra weakness coverage, but Crunch is probably not that useful as even with weakness it only carries 160 power, as opposed to Outrage's 180.