Countering UU/NU Trick Room Teams

Friend and I are arranging a battle. I'd like to say it's casual, but we're way to competitive for that. Got a glimpse of one of his pokemon, and know right away he's going to abuse the hell out of Trick room. Is also fond of Rock and Ground types.
Can a second Trick room undo the first?
Looking for reliable ways to counter a Trick Room team before he can set up a Swords Dancing Rhyperior or something and sweep me.

Another note that I'm sure some of you will enjoy exploiting, he'll probably be reading this thread. :[
Not that he post, fucking antisocial Oregonian.

Pokemon with taunt, since it's likely faster, he'll be forced to just attack you.
You can also get a pokemon thats even slower then those.

Using equally-as-slow Pokemon works. You could also use moves with negative priority, like Revenge and Vital Throw. Those aren't the best examples of good negative priority moves, but they're the first ones I can come up with.

CURSE ON A NON-GHOST TYPE. LOWERS SPEED, INCREASES ATTACK AND DEFENSE.

CURSE ON A NON-GHOST TYPE. LOWERS SPEED, INCREASES ATTACK AND DEFENSE.

Lapras, snorlax, hippowdown make great use of Curse

Already mentioned, but Taunt completely fucks them up.

Taunt, like others have suggested. Mismagius could work. It's fast and is immune to Earthquake/resists Megahorn. A set such as Taunt/Will-O-Wisp/Shadow Ball/Pain Split will Rhyperior up.

Froslass can Taunt and get a free turn of Spikes as well.

Using equally-as-slow Pokemon works. You could also use moves with negative priority, like Revenge and Vital Throw. Those aren't the best examples of good negative priority moves, but they're the first ones I can come up with.

Trick Room doesn't reverse priorities. That being said, moves with priority still go first.

And yes, a second Trick Room undoes the first, but that's not really a reliable counter.

Do Choice Scarfs make pokemon faster or slower under trick? Does it change if they're out when Trick Room is set off compared to if they switch into a tricked room?

Do Choice Scarfs make pokemon faster or slower under trick? Does it change if they're out when Trick Room is set off compared to if they switch into a tricked room?

Slower, and no.

Using equally-as-slow Pokemon works.

This. I used this to my advantage when facing Blue. My Sunflora's speed sucks, so I always ended up attacking first.....