User Aparajita

Hey, just a quick tip, try not to post more than one RMT every few days. Posting several in one day kinda shows that you aren't putting much effort into it. Make a team, test it and get someone to rate it to make sure it's at its best.

Aparajita in hindi means someone who was never defeated right...?

Rhyperior (CB, AV, Offensive SR, Rock Polish)
Cradily (Annoying Stall)
Aggron (Mega, Tank, CB)
Omastar (Shell Smash Offense)
Shuckle (Annoying Stall)
Tyrantrum (Scarf, Band)
Aerodactyl (Lead, Mega)
Golem (Weakness Policy Sweeper)
Tyranitar (Mega, DD, Offensive, Tank)
Crustle (Setup utility)
Aurorus (Specially biased scarf/specs, Physically biased scarf)
Diancie (Mega, Rock Polish, Calm Mind)
Archeops (Sweeper)

Here are my thoughts.
Rock is a physically-biased type normally. Attack and Defense are very high.
Tyranitar is essential. No rock-team can live without him.

Here're a few Pokemon he ought to consider.

Rock is a very diverse type.
Your friend is not that unlucky.