Meet Mortimer: Your Newest Slayer Master

Slayer has always been about adapting to whatever assignment comes your way next. Whether you're chasing XP, hunting unique drops or working towards a particular goal, every Slayer Master offers a different experience.

Following our last blog, many of you asked whether Mortimer would significantly change the way you approach Slayer. Since then, we've been playtesting his mechanics and balancing behind the scenes and, by popular demand, we're ready to share some numbers.

Before we dive into the details, it's worth recapping the intention behind Mortimer's design. Gnome's original proposal explored a system where players would spend Slayer Points to purchase the exact task they wanted. While we loved the idea of giving more agency over assignments, we felt that being able to directly buy tasks pushed too far away from what makes Slayer, well... Slayer.

Instead, we asked ourselves a simple question: how can we offer more meaningful choices without removing the unpredictability that's always been at the heart of the skill?

That's where Mortimer comes in. Rather than choosing any task outright, he'll present you with multiple assignments, each carrying its own modifier. You'll still need to adapt to what's on offer, but you'll have more control over your Slayer journey than ever before.

We're not looking to replace existing Slayer Masters or redefine the most efficient way to train Slayer. Instead, Mortimer should offer an alternative style of play, rewarding those of you who are willing to weigh up choices between creatures, task lengths and bonuses rather than simply chasing a single perfect task and relying generally on Turael skipping.

With Wyrmscraig launching on July 29, it's time to talk numbers and get theorycrafting!

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    About Mortimer

    As a quick recap for those of you who may have missed our previous blog, Mortimer is Gielinor's newest Slayer Master. He's been in the business for a very long time, and let's just say Slayer was a little different back in his day!

Once you've reached Wyrmscraig and gained access to its caverns during The Fallen From Grace quest, you'll be able to unlock Mortimer if you have 100 Combat and 70 Slayer, or 99 Slayer regardless of your Combat level.

Rather than assigning a single Slayer task, Mortimer presents you with two assignments to choose from. As you prove yourself by completing tasks for him, you'll eventually unlock a third choice, giving you even greater flexibility when deciding what to tackle next.

That flexibility comes at a price. Skipping a Mortimer assignment costs a hefty 100 Slayer Points, Turael cannot reset Mortimer assignments, and while using Mortimer you'll only have access to two block slots, each costing 120 Slayer Points. If you receive a task you'd rather not complete, your options are to skip it, store it or finish it before taking on any other Slayer assignment. Task stores are shared with the existing Slayer system, so storing a Mortimer task will use one of your normal store slots.

You'll also have guaranteed modifiers on every task, which should help ensure that each assignment offers something worthwhile, encouraging you to compare the rewards on offer rather than simply hoping for one "best" task!

Mortimer exclusively offers tasks with Superior variants, which should give those of you hunting Superior uniques, such as the Imbued Heart

, more agency over that grind.

    Modifiers

    Every task offered by Mortimer comes with a Modifier, or shall we say... Mortifier. Yes, we loved the suggestion, and it's now referenced in his dialogue!

Modifiers provide additional bonuses to your assignment and can:

• Increase Slayer Points awarded on task completion.

• Increase or decrease task quantity.

• Boost Slayer XP gained from creatures.

• Improve Clue Scroll drop rates.

• Boost your chance to hit the Superior creature unique table.

You'll gradually unlock additional modifiers as you complete assignments for Mortimer.

Task Completion Unlocks

    You'll start with two modifiers unlocked, and as you complete more tasks he'll offer you more.

Tasks Completed Unlock

0Slayer Point Modifier 0Task Quantity Modifier 25Clue Scroll Modifier 50Slayer XP Modifier 75Superior Drop Rate Modifier 100Third Task Choice

    Changes During Balancing

    Originally, modifiers only had a chance of appearing on your assignments. During balancing, however, we found that combining random modifiers with Mortimer's evenly weighted task pool often resulted in assignments that simply didn't feel rewarding enough.

To address this, we've made an important change: every task offered by Mortimer will now always include a modifier. This ensures that every assignment offers something worthwhile and creates much more meaningful variety and choice.

Initially, we loved the idea of all tasks having equal weighting, but this ultimately proved too difficult to uphold during balancing. Weighting is a powerful lever for us to have access to, and we were perhaps a bit too optimistic in our initial design. However, we've still held as close to this as we can, with a few notably strong tasks being reduced slightly to a weighting of 8, while everything else remains at 10.

We've also made a significant change to Mortimer's fifth modifier. Originally, this was designed to increase the chance of encountering Superior Slayer creatures. During balancing, however, we found that improving Superior spawn rates enough to make chasing items like the Imbued Heart

more appealing also had a much larger impact on Slayer XP than we'd intended.

Instead, the fifth Modifier now increases your chance to hit the Superior creature unique table. This lets us improve the grind for specific drops while avoiding being overly disruptive to traditionally AFK Slayer tasks, where lots of Superior spawns might feel frustrating.

Finally, we've added a brand-new creature to Mortimer's task list: Venators. Unlike other Slayer creatures, Venators are exclusive to Mortimer and do not require a Slayer unlock from the Rewards Shop. Instead, they'll become available once you've completed Blood Moon Rises, giving Mortimer another unique assignment to offer.

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    The Important Bit

    Now for the numbers you've all been waiting for.

Every creature in Mortimer's task pool has been individually balanced, meaning each one has its own range of possible modifier values.

Rather than applying one universal bonus across every assignment, we've balanced each creature based on its existing rewards, difficulty and popularity.

Some creatures have better ranges because they're traditionally less desirable, while others receive smaller boosts because they're already among the strongest Slayer tasks available. Our aim isn't to make every task equally efficient, but we do want to ensure every assignment offers a compelling reason to choose it.

Sometimes you'll be choosing between two tasks that aren't particularly exciting. Other times, you'll be spoiled for choice with several fantastic options. We think that unpredictability is part of what makes Mortimer fun!

Below you'll find the proposed modifier ranges for every creature Mortimer can assign.

Each row displays the minimum and maximum values that can roll for that creature's modifiers, including:

• Slayer Points awarded on completion.

• Task Quantity adjustments.

• Clue Scroll drop rate increases.

• Slayer XP bonuses.

• Boosted drop rate from Superiors.

Modifier values increase in increments of five, for example: 25%, 30%, 35% and so on.

Not every creature specialises in the same rewards. Some are stronger for XP, others for clue hunting, Superior encounters or shorter assignments. This is intentional. We want choosing between assignments to be a meaningful decision rather than simply picking whichever task has the largest number.

    Modifier Data Table

Insert the full creature-by-creature modifier table here once the final values are available.

   

Slayer Level Creature Weighting Assign Min Assign Max Extendable Quantity Modifier Points Modifier Clue Scroll Modifier XP% Modifier Superior Unique% Modifier

Min Max Min Max Min Max Min Max Min Max

5 Crawling Hands 10 35 50 No -15 -30 5 15 N/A N/A 25.00% 100.00% 50.00% 100.00%

10 Cave Crawlers 10 35 50 No -15 -30 5 15 N/A N/A 25.00% 100.00% 50.00% 100.00%

15 Banshees 10 35 50 No -15 -30 5 15 75.00% 150.00% 25.00% 100.00% 50.00% 100.00%

20 Rockslugs 10 35 50 No -15 -30 5 15 N/A N/A 25.00% 100.00% 50.00% 100.00%

25 Cockatrice 10 35 50 No -15 -30 5 15 75.00% 150.00% 25.00% 100.00% 50.00% 100.00%

30 Pyrefiends 10 35 50 No -15 -30 5 15 75.00% 150.00% 25.00% 100.00% 50.00% 100.00%

45 Pyrefiends 10 35 50 No -15 -30 5 15 75.00% 150.00% 25.00% 100.00% 50.00% 100.00%

50 Bloodvelds 8 120 180 Yes 50 100 10 15 35.00% 75.00% 5.00% 15.00% 100.00% 150.00%

51 Gryphons 10 80 120 Yes 50 100 10 25 75.00% 150.00% 20.00% 50.00% 100.00% 150.00%

52 Jellies 10 80 120 No 50 100 10 15 35.00% 75.00% 5.00% 15.00% 100.00% 150.00%

54 Custodian Stalkers 8 80 120 Yes 50 100 10 15 N/A N/A 10.00% 25.00% 100.00% 150.00%

55 Turoth 10 80 120 No 30 80 15 30 75.00% 150.00% 35.00% 75.00% 200.00% 300.00%

56 Warped Creatures 10 80 120 No 50 100 10 15 35.00% 75.00% 5.00% 15.00% 100.00% 150.00%

58 Cave Horrors 10 80 120 Yes 30 80 15 30 75.00% 150.00% 35.00% 75.00% 200.00% 300.00%

60 Aberrant Spectres 10 80 120 Yes 30 80 15 30 75.00% 150.00% 35.00% 75.00% 200.00% 300.00%

60 Basilisks 10 40 60 Yes 50 100 25 40 75.00% 150.00% 35.00% 75.00% 200.00% 300.00%

62 Wyrms 10 80 120 Yes 50 100 25 40 75.00% 150.00% 35.00% 75.00% 200.00% 300.00%

65 Dust Devils 8 120 180 Yes 50 150 10 15 N/A N/A 10.00% 20.00% 100.00% 150.00%

70 Kurask 10 40 60 No 30 80 25 40 75.00% 150.00% 35.00% 75.00% 200.00% 300.00%

74 Venators 10 120 180 Yes 50 100 10 25 75.00% 150.00% 35.00% 75.00% 50.00% 100.00%

75 Gargoyles 10 120 180 Yes 50 100 15 30 75.00% 150.00% 35.00% 75.00% 200.00% 300.00%

78 Aquanites 10 40 60 Yes 50 100 25 40 75.00% 150.00% 35.00% 75.00% 200.00% 300.00%

80 Nechryael 8 150 200 Yes 50 100 10 20 35.00% 75.00% 35.00% 75.00% 200.00% 300.00%

84 Drakes 10 40 60 No 30 80 25 40 75.00% 150.00% 25.00% 75.00% 75.00% 150.00%

85 Abyssal Demons 8 120 180 Yes 50 100 10 25 75.00% 150.00% 10.00% 25.00% 30.00% 60.00%

90 Dark Beasts 10 40 60 Yes 30 80 10 25 75.00% 150.00% 35.00% 75.00% 200.00% 300.00%

92 Araxytes 8 120 180 Yes 50 100 10 20 35.00% 75.00% 5.00% 15.00% 10.00% 25.00%

93 Smoke Devils 8 80 120 No 50 100 10 20 35.00% 75.00% 5.00% 15.00% 10.00% 25.00%

95 Hydras 10 150 200 No 50 100 15 30 75.00% 150.00% 10.00% 30.00% 75.00% 150.00%

If you'd prefer to browse the data yourself, we've also provided it in Google Sheets format.

We can't wait to see the community dive into the numbers, optimise new routes and discover how Mortimer fits into your Slayer journey!

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    FAQ

    How do task extensions and unlocks work with Mortimer?     Task extensions will work for Mortimer, but task unlocks that specify certain masters will not. You'll have access to Gryphons, Aquanites, Basilisks and more from the get-go, without needing to invest Slayer Points to unlock them.

    Do all unlocked modifiers have an equal chance of appearing?     Yes. Once you've unlocked a modifier type, it has an equal chance of appearing on your assignments.

    Can multiple task choices have the same modifier?     Yes, different tasks can have the same modifier.

    Can I be offered the same creature more than once?     No. Mortimer will never offer duplicate creatures within the same set of task choices.

    Why aren't all Slayer XP bonuses the same?     Slayer tasks already vary significantly in efficiency. Rather than applying a flat bonus across the board, we've balanced XP modifiers individually for each creature.

    How will Mortimer affect existing Slayer Masters?     Mortimer isn't designed to replace Duradel, Konar or any other Slayer Master.

While he's intended to reduce the reliance on Turael skipping, that remains a perfectly valid way to approach Slayer if it's what you enjoy.

Duradel and Mortimer are also currently extremely close in terms of XP per hour. Over time, Duradel should continue to improve as more block slots are unlocked and eventually secure a lead over Mortimer. He offers tasks Mortimer cannot assign, notably providing access to many more boss tasks. These can be completed on-task and may appeal to Iron players, Collection Log hunters and pet hunters alike.

Mortimer offers a different style of gameplay, rewarding those of you who enjoy weighing up multiple assignments, modifiers and task lengths.

    What's the expected impact on the Imbued Heart

?     We're happy to confirm that Mortimer should become the new best Slayer Master for the Imbued Heart

compared with current metas where players use Turael to skip for Araxytes and Smoke Devils at Duradel. Players currently place this at around 80 – 100 hours for an Imbued Heart

at the top end. Mortimer should be somewhere in the 65 – 80 hour ballpark, also at the top end, once his third task selection has been unlocked.

You'll still be doing your fair share of Araxytes and Smoke Devils on this grind. Those tasks are incredibly strong when it comes to getting the Heart. Between those tasks, we expect you'll complete fast Mortimer tasks and occasionally select a task with a Superior modifier active. It's worth noting that in-game rates can vary drastically based on efficiency, including factors such as gear, blocks, skips and whether you choose to use slaughter or expeditious bracelets.

Regardless of any increase to Hearts per hour, we're confident that completing tasks for Mortimer should feel like a breath of fresh air for Slayer and shake up how the skill feels to engage with!

    How do modifiers interact with existing boosts?     Modifiers are applied to the base value for each effect rather than stacking with other bonuses. Existing bonuses are then applied to that updated value.

    Does the Slayer XP modifier also affect Superior Slayer monsters?     Yes. The Slayer XP modifier increases the Slayer XP awarded by Superior Slayer monsters as well as their regular variants.

    Is the Task Quantity modifier a percentage or a flat adjustment?     The Task Quantity modifier is a flat adjustment, not a percentage. If your task has a Quantity modifier of -50, your assignment will contain 50 fewer creatures than normal. Likewise, a +50 modifier will increase the assignment by 50 creatures.

    Will task storage work?     Yes. Task storage will let you store the selected task and its modifiers.

    Will the Slayer Cape perk also work?     Yes. You can still get a 10% chance to be reassigned the same task, with the same task length and modifiers.

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You can also discuss this update on the 2007Scape subreddit, the Steam forums, or the official OSRS Discord. For more information, check the official Old School Wiki.

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