Both FAQs list Riolu as learning Force Palm at 15 and the one that talks about level 11 mentions Counter being learned at that level.
Anyway, as others have said, Counter is really all you need. One Work Up + Tackle from either of Cheren's Pokemon will be the downfall of themselves because Riolu can at least take one Tackle and Counter it for massive damage. Personally, I used the swap to heal Riolu and have my other Pokemon Tail Whip and hit the Lillipup down enough that Riolu could one hit with Quick Attack but not enough for Cheren to use his Potion.
Why would you use the FAQs on this site? Text documents are user unfriendly. Just go to Serebii.
I... don't? I just checked them to see what the TC was talking about. I've already gone through White 2 Japanese version blind. :s
I tryed counter spam he work up 3 times and killed riolu so no counter (i wasnt countering after the first work up just used quick attack as it was that or counter on my move set --- Pokemon white fc 0820-0308-4093 member of ace breeding center breeder and founder of the dw breeding center
I doubt counter spam will work in challenge mode as he would probably just set up on you. Just thank god that the Pidove e gains won't have gust. --- Never rub another man's rhubarb. My hypocrisy only goes so far.
What you can do is use the x defend on Riolu so it can survive the +3 trackle. Cheren apparently didn't keep track of it. Of course my riolu being impish may have had something to do with it. --- The Offical Groudon Oof the POkemon Black and White 2 Boards.