OSRS Yama Contracts for Oathplate: Bossing Guide

Game screenshots and facts are cited from the Old School RuneScape Wiki (strategy, equipment, drops, and related pages). Writing is original editorial, not a copy of the wiki article.

Yama's contracts turn a mid-tier demon fight into an oathplate grind with layers of risk, contribution tracking, and specific contract variants. If you're eyeing oathplate armour, you are not just farming a boss—you are deciding between direct unique rolls, shard crafting, and negative-profit contract runs that guarantee progress. This guide covers what to expect before you commit hours, from the unlock chain and death fees to the math behind 450 shards and 1/600 armour pieces.

The base encounter is duo-friendly like the Royal Titans, but several contract versions push you into solo or modified mechanics. We'll walk through the mechanics that actually end trips, gear rungs that matter, and when a paid carry saves more than it costs.

Yama Contracts and Oathplate: What You're Signing Up For

Yama is a demonic duo-focused boss found in Yama's Domain at the bottom of the Chasm of Fire. His base fight emphasises movement and prayer switching, designed as a step up from the Forgotten Four. You can fight him solo or with a partner, and loot is distributed based on damage dealt—similar to Royal Titans, but with more punishing individual contribution thresholds.

The unique reward space is what draws most players: Yama drops pieces of oathplate armour, the soulflame horn, dossiers, forgotten lockboxes, and oathplate shards. Oathplate armour requires level 78 Defence and is slash-accuracy focused, making it a serious upgrade for high-defence slash-weak bosses like Vardorvis, Duke Sucellus, Verzik Vitur, and even Yama himself.

Tradeable contracts modify the fight and the reward structure. The Contract of Glyphic Attenuation, for example, raises Yama's health to 2,875, gives him +80 crush defence and +666 all other defence bonuses, reduces glyph protection from 10 ticks to 3, and makes you take 3x more damage when absorbing a Glyph of Fire. It is consumed on entry, but you get it back if you win—and it progresses you toward the purifying sigil for radiant oathplate.

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Requirements and Unlock Checklist

Before stepping into Yama's Domain, make sure the account meets the quest and skill gates. The fight itself has soft stat recommendations, while crafting oathplate from shards has hard skill requirements.

Oathplate crafting is a meaningful alternative to direct drops, but it is not cheap. Each piece requires 9 infernal plates made from shale and shards, earning roughly 22,000 Smithing xp per piece. The shards come from Yama, while shale is mined separately. Because the armour counts as Zamorakian gear in God Wars Dungeon, it doubles as utility for GWD trips.

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Fight Overview: The Mechanics That Kill Players

Yama's combat achievements read like a list of ways to die. The fight has a judge mechanic that punishes attacking with the wrong style, forced exile from the arena, a shadow crash attack where you need to be close to the centre, fire damage, and void flares that must be killed with special attacks.

The base encounter is not forgiving. Mistiming a prayer switch or misjudging the shadow crash centre is usually lethal. Without a partner, you have to manage every mechanic yourself; with a partner, you still need to pull your weight because contribution directly scales your reward chances. Below 375 damage (15% of his health) you roll the junk table instead of the unique chain.

The Contract of Glyphic Attenuation makes the fight worse in specific ways: better defences, shorter glyph protection, and 3x fire absorb damage. That contract is not a first-kill goal; treat it as a later challenge or a boost target.

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Gear Rungs: From Budget Slash to Oathplate Itself

Before you own oathplate, bring the best slash-accuracy gear you can afford. Oathplate's strength bonus is on par with Bandos plus a Neitiznot faceguard, but its real value is +38 slash attack across the set and very high slash/magic defence. Compared to Torva, it trades raw strength and prayer bonus for slash accuracy and better slash/magic defence—against high-defence slash-weak targets, that accuracy often wins.

If you are grinding Yama specifically to obtain oathplate, remember that the armour is also best-in-slot for many slash-weak bosses. Once you have it, your next upgrades become easier. For the Yama fight itself, standard high-level melee or ranged setups work, but check a current strategy page for exact switch recommendations—Yama's mechanics punish slow gear swaps as much as poor prayer.

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Trip Length, Death Fees, and Supply Burn

Early trips are short. Expect to die while learning the judge and exile patterns, and the reduced reclamation fee until 10 KC cushions some of that cost. Once you can consistently avoid the shadow crash and fire, a single inventory of supplies will last much longer. The base fight rolls standard loot, but many contracted fights do not roll the standard table at all—they replace it with guaranteed contract rewards.

Method	Approx Hourly Profit	Notes
Killing Yama (solo)	5,039,335	Base fight, no contract cost, standard loot table.
Contract of Shard Acquisition (duo)	13,174,957	Requires duo; shard-focused rewards scale with contribution.
Contract of Oathplate Acquisition	−10,493,512	Guaranteed oathplate progress but expensive to run.
Contract of Catalyst Acquisition (duo)	4,156,569	Duo catalyst rewards, moderate profit.
Contract of Harmony Acquisition	−2,372,306	Negative profit harmony variant.

These figures come from the OSRS Wiki money making guides and assume efficient kills. If you are not hitting those speeds, your supply burn per kill will be higher and your profit lower. The negative-profit methods still cost money, so plan your budget before buying contracts.

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Common Mistakes That Inflate Your KC

Most players waste time at Yama with avoidable errors. A few of the most frequent:

• Under-contributing in duo: Below 375 damage rolls junk; lower contribution scales down unique chances. Do not leech—you get nothing but a fast death.
• Wrong style on the judge: The judge punishes incorrect attack style. Pay attention to its protection or indication.
• Standing too far from the shadow crash centre: The achievement requires being within one tile of the centre; the mechanic itself likely punishes distance.
• Ignoring void flares: These must be killed with special attacks. If you do not have special attack energy, you take avoidable damage.
• Healing or drinking potions carelessly: Several combat achievements restrict food to plain pizza and ban potions entirely. If you are not aiming for those tasks, fine—but know the restriction exists.
• Losing Item Retrieval Service contents: Dying at Yama wipes IRS. Do not store untradeables in a deathbank before this fight.
• Missing the yellow sigil window for demon contract drops: Contract of Glyphic Attenuation drops from demons in the Chasm of Fire only when the killing blow is a special attack, with a 5x boost while the yellow sigil is active.

Fix these and your effective kill count—and profit per hour—improves quickly.

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Drop Table, Contracts, and Oathplate Math

Yama's drop system is sequential and contribution-scaled. If you deal at least 375 damage, you roll 1/120 for the unique table. That unique table gives 3/5 oathplate armour piece and 2/5 soulflame horn. If you miss, you roll 1/12 for a dossier, then 1/30 for a forgotten lockbox, then 1/15 for 12 oathplate shards. If all those fail, the standard table is rolled—unless you are under a non-Familiar contract, where the standard table is skipped entirely.

Effective solo rates at 100% contribution are roughly: each oathplate piece at 1/600, soulflame horn at 2/600, dossier at 1/12.1, forgotten lockbox at 1/33, and shards at 12 per 1/17.07. Duo rolls are individual and scale by contribution, so two players can both receive uniques from the same kill if they both contributed enough.

For oathplate specifically, direct pieces are the jackpot but rare. Crafting is the deterministic path: 450 shards per piece, which means 1,350 shards for the full set if you go dry on direct drops. At a solo 100% contribution rate of about 0.70 shards per kill, that is roughly 1,900 kills—long, but guaranteed progress. The Contract of Oathplate Acquisition exists to make that progress faster, but it costs about 10 million gp per hour in losses according to the wiki money making guide.

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KC Goals and Combat Achievement Targets

Yama's combat achievements give you clear milestones:

• 1 KC — Yama Adept (Elite, 4 points)
• 50 KC — Yama Veteran (Master, 5 points)
• Under 3:38 average — Yama Speed-Trialist (Elite, 4 points)
• Under 3:00 average — Yama Speed-Chaser (Master, 5 points)
• Under 2:34 average — Yama Speed-Runner (Grandmaster, 6 points)
• Contractually Unbound — Defeat Yama under elevated conditions of a non-standard contract (Grandmaster, 6 points)

Completing all tasks requires perfection-level play: Shadow Dancer, Fire Fighter, Back so soon?, and no avoidable damage for the Grandmaster Contract Choreographer task. Those are not casual grinds. If you only need oathplate, 50 KC is a reasonable checkpoint to aim for before deciding whether to continue.

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When a Quote or Carry Makes Sense

Yama is not a boss you want to brute force with low stats and no plan. A paid carry or duo boost is reasonable in a few cases:

• You want the 50 KC milestone for Yama Veteran and do not want to spend 10–15 hours learning mechanics.
• You need Contractually Unbound but cannot clear a modified contract solo.
• You want Oathplate armour and the negative-profit Contract of Oathplate Acquisition is unattractive; a fast partner increases kills per hour, spreading the cost differently.
• You are a Hardcore or Group Ironman and cannot risk the dangerous death—a carry avoids that risk entirely.

However, because drops scale with contribution, a carry will not hand you uniques if you deal almost no damage. It saves time on KC, death fees, and combat achievements, not on the drop grind itself. If your goal is oathplate, buying shards or paying for a high-efficiency duo partner is often cheaper than losing 10m per hour on a solo contract.

Get a service quote if you want a realistic cost comparison before committing hours.

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Sources

• Yama - OSRS Wiki
• Contract of Glyphic Attenuation - OSRS Wiki
• Oathplate armour - OSRS Wiki