Tapu Koko
Nature's Madness
Discharge
Aerial Ace
Dazzling Gleam

Pheromosa
Brick Break
Lunge
Bug Buzz
Ice Beam

Xurkitree
Signal Beam
Dazzling Gleam
Thunder
Charge Beam

In retrospect I should've used Tapu Bulu.

Yeah, that would of solved some of the problems.

Seriously, just chill out and attack it calmly. Even when you fail, you'll at least be able to figure out your mistakes... Although, why you have Brick Break AND Lunge on Pheromosa, as well as Charge Beam and Thunder...

I'd recommend at least swapping out the Charge Beam for Tail Glow. Set-up with a +3 and wreck anything that gets in your way. Probably change Thunder out for Tbolt, just to guarantee damage.

Pheromosa had decent ATK so Brick Break was actually doing pretty well, especially when Beast Boost kicked in, plus I was facing a bunch of Fighting-weak Pokémon so that helped too.

Sorry, I'm a bonehead. I forgot Lunge is bug-type. Although it still raises the question of why you've got Bug Buzz as well. Probably should replace that with Poison Jab for Fairy coverage, as it resists both your Stabs. You might also want to change Lunge out for U-Turn so you can switch and deal damage.

Yes that would be the better choice. If you have a good team from X,Y,Ruby,or Sapp you would have better chances of winning. Also sometimes it the luck of the draw to win you know critical hit or super effect moves. Try trading I sure it could be a bit of help.

Well I could ditch Ice Beam for Poison Jab on Pheromosa, but Lunge is doing pretty good too.

I'm done. I give up.

Someone please trade with me or else I'm gonna resort to hacking for them.

No one's going to trade one of a kind items, especially ones that are highly valuable in competitive battling and have to be earned through post-game content.

I mean, frack, I lost count of how many times I failed in the tree before I got them.

Go ahead and hack them if you're that desperate, no skin off anyone else's nose.

Whatever, Plan X it is then.

Hate to say it man but this really is your fault. For one, you haven't been clear if these guys were EV trained
Second, why are Taku Koko and Pheramosa both mixed attackers? It's better to focus on just one stat
Third, what items did they have if any? Items are very valuable in the Battle Tree
Fourth, why does Xurkitree have both Thunder AND Charge Beam? Same goes for Pheramosa having 2 Bug moves
Fifth, Tapu Koko's most commonly used as a hard hitting special attacker, why is Nature's Madness there?