Mega Medicham uses the Pure Power Ability, which doubles its attacking power in battle.
Mega Medicham can be obtained by using the Mega Stone while Medicham is holding a Medichamite in battle.
Mega Medicham has yet to appear in a Spin-Off game as of writing.
Trading Card Game
Mega Medicham resides in the Overused (OU) tier of competitive battling. Due to Pure Power, Mega Medicham is among the tier's most ferocious wallbreakers, capable of destroying many Pokémon with its STAB High Jump Kick and Zen Headbutt. Those attacks allow it to tear apart some troublesome physical walls like Skarmory, Hippowdon, and Clefable with relative ease. It is frail and is outsped by many prominent threats like Latios and Keldeo, making it hard to use against offensive teams, but with priority in Fake Out, it can whittle away at those threats and give an opening for other Pokémon to take advantage of the weakened Pokémon. Despite top-tier power, Mega Medicham is hampered by the common use of its counters like Mega Sableye and Slowbro and faces competition from other Mega evolutions like Mega Lopunny.
Related ThreadsHelp with Mega Medicham moveset and ev's - last post by @ Jul 27, 2014
[SPOILER]Mega Medicham,Bannete,Pinsir - last post by @ Oct 11, 2013
I need help on which mega to use - last post by @ Feb 16, 2014
Mega Evolves Breakdown/Speculation *Spoiler Alert* - last post by @ Nov 6, 2013
Gen 3 Mega Stats - last post by IamthebestNever @ Aug 9, 2014