Heyo, I have created this guide for the people who didn't know about the grinding spot Olun's Valley, which is the best place to grind for getting the La Orzeca Armor Costume.

Note: This place is not for the new adventurers.

1. Olun's Valley Stats:
Region: O'dyllita

Location: Olun's Valley.
Node: Olun's Valley.
Recommended AP: 300.
Party of 3 Recommended
Trash Loot Value: 107k.
Money/Hour: 200-300mil.

Experience: 1/5.
Silver: 4/5.

2. La Orzeca Armor Costume Showcase & Explained:

This is a screenshot of my Shai with the La Orzeca Armor Costume on. (Search on Google if you want to see more pictures with it.)

To get the La Orzeca Armor Costume you need the Quturan's Right Lung, the item can be dropped by the golems but is really rare, but you can also get 100 Quturan's Ashen Leaf, and do Simple Alchemy with them to obtain the Quturan's Right Lung.

= Quturan's Ashen Leaf

= Quturan's Right Lung

Note: You can create a crystal slot in the costume.
Note: Olun's Valley isn't the only place where you can get these items, but the best place to get them.
Note: There is a helmet, but the helmet can not be obtained in Olun's Valley.

3. Olun's Valley Information:

First, I can say that you don't need 300ap.

The spot works like this: You have 2 DPS classes that are doing most of the damage on the golem, and then you have a Shai who buffs the DPS classes, and also debuffs the golems.

Gear recommendations: I would say as a Shai you could go there with the lowest 269-275kutum AP, but expect people can/will reject you sometimes. As a DPS class, I would say 281kutum AP as the lowest, but maybe if you're a Succession Lahn or a Succession Striker with double Blackstar or something like that, you would maybe have a chance with lower AP. For DP, I would recommend if you want to be a safer go with around 350DP, but is more about dodging than actual tanking the golem, so you can go with less DP if wanted to.
I feel like it's almost mandatory having a Shai in your party, but if you really can't find anyone, then you can go 3 DPS, just make sure that you have a high -evasion skill in your party.
When grinding here, use Blue Loot Scrolls with Agris Fever On! You're only going to get good money with that. (You're only going to use around 10k Agris Fever Points for every hour grinding here.) If you have run out of Agris Fever, you can use Yellow Loot Scroll, but won't be as beneficial.
If you want more drop rate for getting the leaves faster, I recommend investing energy into the node, plus you can buy Adventurer's Luck from the tent, and/or go on ArshaPvP.
Do not underestimate the minions! (Yes, they can do a lot of damage, stun and do knockdowns... WATCH OUT!)

4. Olun's Valley Item Drop

We have the trash loot with the value of 107k each.
Both Black Stones drop here.
A lot of Caphras & Ancient Spirit Dust drops here too.
Olucas, the item used to craft Olucas Crystal (Awakening PvP Crystals.)
Quturan's Right Lung & Quturan's Ashen Leaf, both used to get the La Orzeca Armor Costume.
Venomous Night Fang, combine to get the Ibedor's Scroll.
The Rich Merchant's Ring Piece #5 can also be obtained here in Olun's Valley.

5. Safe Spot

Below here is a video that will guide you to the Safe Spot from O'draxxia Storage NPC, where you will want to buff, repair, turn on agris, etc...

6. Buffs
These are the buffs I would recommend you to use while grinding Olun's Valley:
Meals: Simple Cron Meal (For being tankier) or Exquisite Cron Meal (For having more DPS)
Villa Buff: Body Enhancement.
Turn on Alchemy Stone!
Perfume: Use Khalk's Elixir if you want to be tankier, but else use Perfume of Courage. (Use Elixir of Deep Sea to get the highest trash.)
Church Buff/House Buff/Horse Buff/: You can use these buff for more DPS and get a bit tankier, but not necessary.
Elixirs: Use these elixirs below! Do Not Use Draughts!

Note: The Sharp Detection is hard to get, but you can grind without it. (Try to get it, is very useful.)

7. Mechanics/Technique & Main Rotation:
Some things are a bit hard to explain, so I will link videos that are helpful too, but overall you want to dodge all the red aoe's and not get hit, if you're going to get hit, try to block with Forward Guard and NOT Super armor.
Make sure you're hitting Back Attack at all times, so turn on "Attack Decisions" (Is under Show/Hide in General Settings.)
You will need one of the Party Members to prepull the next golem in your rotation, before the golem you're killing dies, I would recommend having the Shai to prepull, or having the Player with the lowest AP do it.

If you want to learn more about the Golems attack pattern, watch this video by Engeli Heart (Please watch it)

Now I want to show you a picture of the main rotation with the places where you should be baiting the arm and where the back attack is. (More explained at 7. More Mechanics (Perfect Pull))
If you're not over clearing, then I wouldn't add number 4 and number 8 golem in your rotation.

Below is there a video by Jaycoon explaining the Arm Back Attacks. (Please watch it)

8. More Mechanics/Technique (Perfect Pull)

If you want to pull the highest trash possible, then you have to do the Perfect Pull Technique, it works like this: You want to DPS the Golem until it HP Bar hits in front of G, and then wait for the Golem to do a new attack, to then DPS it below the N, this will skip forward, so the Golem will spawn the new minions, and will go directly to the arm smash, then you will have to stand in the Bait Location, and make sure you back attack the arm and kill it in the first try. (The arm is "bugged" so there isn't always a back attack behind the actual arm.)

Note: This only works right if you have Display Knowledge turned off.

If your Party isn't that good at perfect pulling, then it's alright to just DPS it normally.
If you don't perfect pull, then I wouldn't recommend killing the arm at the first strike, because if you do, you will lose the iframe moment, where you can DPS the minions and not the golem. A lot of times when I haven't done a perfect pull, but still killed the arm on the first strike, we would end up killing the golem, before the minions. (The minions will despawn if you kill the golem before killing the minions)

9. More Mechanics/Technique (Shai-BSR-Method)

So the Shai Black Spirit Rage Method, is quite simple, you just give your black spirit to the Shai in your party, so she can do the Z Buff, at all the golems in your rotation. This method should give you more profit grinding here.

10. Afuaru, The Graverobber
While grinding Olun's Valley, are you going to get a lot of Afuaru spawns, they have a high chance of dropping the leaves, so they're 100% something you need to kill when spawning, but don't rush out and go for the Afuaru when it spawns, wait for a long animation attack from the golem, or wait till it dies. (Afuaru's won't disappear when it hasn't been hit, if you see it running away, let your party know, and hunt it down)

Tip:
Please make sure everyone in your party knows what elixirs to use and not to use, and make sure everyone knows that you're trying to perfect pull or not.
You can go on Discord or anything likely to be more coordinated, but is not necessary.

Now go grind that costume, I hope you'll get it fast, and not lose too many crystals.

Thanks for reading/using my guide, I hope it helped you on your adventure in Black Desert, if I got any mistakes, or you feel like I'm missing something, please contact me on Discord: Nootsi#0001.

Have a great day! :3

Nice guide! I don't have the AP for Oluns yet but it's something I definitely want to do in the future for the Costume so it's nice to read up on how things work there. 

Great guide Nootsi! You're the boss :)

Nice guide!
Another helpful tip I would give, is if you're afraid of the spot or losing your main crystals,
tag a character to grind it with! (Do learn the basics of the new class before you go grind)
Most cases it can be cheaper to completely re-tag your character than replacing all your main crystals
assuming you die a lot trying to learn the golem mechanics.
And trust me, you will die even if you have the recommended gear for it!
If you do want to tag a character to grind golems with, do consider tagging a shai.
Not only shai needs less gear than DPS classes, is very cheap to tag, its also rather fun to learn how to grind with it.
And of course you're giving your party a massive advantage buffing them, and debuffing the monsters.

I'm suggesting tagging a shai also because not many people grind oluns valley anymore. It WILL help you find a party.
Majority of the geared players have their outfits (or merchant ring pieces) already,
and its not considered "worth to grind" money wise anymore.
When Elvia hunting grounds got released and all other spots caphras stone droprates got increased,
its just too high risk for "no reward" for many people when they could be making more silver/hr in way safer spots.

Again thank you for guide, and I hope all of you will enjoy the grindspot and get your outfits/ring pieces fast! ^^