Yama and Oplate: why this boss is worth understanding

Yama stands out as a high-value boss because Oplate armor pieces hold strong market value and also serve as excellent slash-focused gear for self-sufficient accounts. What makes Yama especially interesting, though, is not just profitability—it’s how the loot system is built from multiple overlapping sources that change the “feel” of the grind.

Instead of relying on a single rare drop, Yama’s Oplate progression comes from four parallel paths: direct uniques, a lockbox roll, shard-based crafting, and contract-based guarantees. Together, these create a form of practical dry protection while still preserving the excitement of big drops.

All four ways to obtain Oplate from Yama

There are four distinct routes to an Oplate armor piece. Understanding how they stack is the key to estimating how long you’ll realistically be at Yama.

1) Direct Oplate piece drop

This is the standard “boss drops the item” method. In a solo kill where you deal 100% of the damage, the chance to receive any Oplate piece is 1/200. Since there are three pieces, that implies 1/600 for a specific piece on average.

In group kills, the direct-piece chance scales with contribution. In a duo where you deal 50% of the damage, your effective chance becomes 1/400 for any piece (and roughly 1/1200 for a specific piece).

2) Forgotten lockbox (secondary Oplate roll)

Yama can also drop a Forgotten lockbox at a rate of 1/33 per kill. When opened, the lockbox has its own independent chance to award an Oplate piece: 3/43 for any piece.

Multiplying those together gives an effective per-kill Oplate chance from lockboxes of 1/4433. That looks small, but it matters because it does not scale with damage contribution—meaning it becomes relatively more valuable the less damage you do in a duo.

3) Oplate shards (crafting + dry protection)

Yama also drops Oplate shards. Collect 450 shards and you can create any Oplate armor piece you want. Shards come from two places:

• Direct shard drops from Yama, where quantity scales with damage contribution.
• Shard drops from the Forgotten lockbox, where quantity does not scale with contribution.

This is the system’s “soft pity.” You can still be unlucky on shard quantity, but it dramatically reduces the odds of extreme dry streaks compared to pure unique hunting.

For players capable of consistently completing contracts, there’s a high-skill route to guaranteed progress:

• Yama has a 1/12.1 chance to drop King Roel files.
• Within those files, there’s a 1/133.8 chance to obtain the Contract of Oplate Acquisition.
• Completing that contract awards a guaranteed Oplate piece.

There’s also a Contract of Oplate Shard Acquisition, which further accelerates shard progress if completed reliably.

Baseline math: how long would direct drops take?

If you only cared about direct Oplate piece drops, you’re dealing with a “collect all three” problem—getting a full set is not just three successes, because duplicates happen. This is a classic coupon-collector situation.

Using the standard approximation for three unique pieces, the average solo killcount to complete the full set from direct drops alone is about:

• ~1,100 solo kills (with 1/200 for any piece)

In a duo where you do about half the damage, your direct-drop rate halves, so the average killcount roughly doubles:

• ~2,200 kills at ~50% contribution
• ~1,800 kills if you can push ~60% contribution

On killcount alone, solo looks better. But kill time changes the conclusion.

Solo vs duo: when time-per-kill matters more than drop rate

A practical comparison depends on how fast you kill Yama in each setup. A common benchmark is:

• Solo melee: ~6 minutes per kill
• Duo melee: ~3 minutes per kill

With those assumptions, direct-drop-only grinding comes out roughly similar in total hours for solo vs a 50/50 duo, because the duo kills twice as fast but your personal unique rate is halved.

The key point: if your contribution is meaningfully higher than your partner’s (for example, ~60%), duoing becomes clearly better in hours because you retain more of the personal drop chance while still enjoying faster kills.

Take a look at: a beginner-friendly breakdown of group roles and coordination

How the Forgotten lockbox flips the duo equation

The lockbox is the first major reason Yama “wants” you to group. Its drop rate does not care whether you did 100% of the damage or 10%—you still get the same 1/33 chance for the box per kill, and the same chance at an Oplate piece inside it.

That means:

• In solo, the lockbox slightly improves your effective “any piece” odds (from 1/200 to about 1/191).
• In duo, it improves your overall progress more relative to your scaled-down direct-drop chance.

When you add lockboxes into the model, duoing begins to look better on time even at a 50/50 damage split, because some of your progress is now coming from a source that doesn’t get penalized by contribution.

Why Oplate shards are the real MVP: dry protection that still feels like RNG

Pure rare-drop grinds have a familiar problem: the long tail. Even if the average completion is reasonable, a meaningful slice of players go wildly dry—several times the expected rate—because there’s nothing to “pull” them back toward completion.

Oplate shards change the distribution. Instead of a single broad peak with an ugly tail, the shard system compresses the worst outcomes. You still have variance, but the truly brutal “thousands of kills past rate” scenarios become far rarer.

In the scenario that includes lockboxes and shards (but ignores contracts), the average completion estimates improve dramatically:

• Solo: roughly ~641 kills on average
• Duo at ~50% contribution: roughly ~1,200 kills on average

Those killcounts look far apart until you remember the time-per-kill difference. With faster duo kills, the hours can favor duoing even when your personal contribution is only half.

If you’re consistent at completing contracts (and you don’t fail them), they provide a real speed-up because they inject guaranteed progress into the system.

When contracts are included as “always completed successfully,” average completion estimates improve again:

• Solo: about ~550 kills on average
• Duo at ~50% contribution: about ~1,040 kills on average

In other words, contracts don’t just help a little—they shave a meaningful chunk off the grind, especially for players already pushing efficient kills.

Practical time-to-complete expectations (melee vs mage, solo vs duo)

To translate killcounts into something you can plan around, use realistic kill-time assumptions. A useful set of benchmarks is:

• Melee solo: ~6 minutes
• Melee duo: ~3 minutes
• Mage solo: ~7 minutes
• Mage duo: ~3 minutes 30 seconds

Assuming a duo where you average ~50% contribution and ignoring contracts (a common “most players” scenario), the general ranking for fastest completion tends to be:

1) Melee duo (fastest on average)

Expect around ~59 hours on average. The middle chunk of players often finishes in roughly the ~45 to ~72 hour band, while very unlucky outliers can push beyond 100 hours.

2) Melee solo

Typically around ~64 hours on average, with a broad middle range and a smaller but still real chance of a long grind if RNG runs cold.

3) Mage duo

Despite being a duo, slower kill speed can put this behind melee solo, averaging around ~69 hours for completion.

Usually the longest route, averaging around ~75 hours, with the worst-case outliers stretching much further.

The takeaway is simple: if you’re currently doing slower solos, shifting into a faster duo setup can save a noticeable amount of time even if your personal direct-drop rate is lower.

So… is Yama better solo or duo?

With direct drops alone, solo and duo can be similar in total hours if duo kill speed is about double and contribution is split evenly. But once you include Yama’s other reward layers, duoing becomes increasingly attractive:

• Forgotten lockboxes don’t scale with damage, making duo kills relatively more rewarding for lower contribution players.
• Shards shorten the grind and reduce extreme dry streaks, and lockbox shards also ignore contribution scaling.
• Contracts reward consistency and skill, further reducing time-to-complete.

In practice, melee duo tends to be the best overall blend of speed and progress for most players—especially if you can keep deaths low and maintain steady contribution.

Why Yama’s drop design feels better than many bosses

Yama’s system is a layered solution to three common problems in bossing grinds:

• Encouraging group play: the lockbox provides meaningful value that doesn’t punish lower contribution.
• Reducing extreme dryness: shards create a soft backstop without removing RNG excitement.
• Rewarding mastery: contracts give skilled players a way to convert performance into faster completion.

Instead of a hard “guaranteed drop at X kills” or strict duplicate protection, the shard approach preserves variance while making the worst outcomes less common—often a more satisfying balance for long grinds.

Frequently Asked Questions

Is it ever worth soloing Yama for Oplate?

Yes. If you have strong gear, stable kills, and your duo options are inconsistent (slow kills, frequent deaths, or low uptime), solo can be competitive. The gap usually comes down to kill speed and reliability.

No. The lockbox drop chance per kill stays the same regardless of your contribution, which is why duoing benefits more once lockboxes are considered.

Are Oplate shards “guaranteed” dry protection?

Not in a strict sense. You can still be unlucky on shard drops, but collecting toward 450 significantly reduces the odds of extremely long dry streaks compared to relying on rare pieces alone.

How much do contracts matter for completion time?

If you can complete them consistently, they meaningfully reduce the average killcount by injecting guaranteed progress (either a guaranteed piece or extra shard gains).

What’s the best general approach for fastest completion?

For most players, a fast melee duo with steady contribution and low deaths tends to produce the best average completion time, especially once shards and lockboxes are factored in.