The dwarf multicannon, or simply the cannon, is arguably the most significant investment an Old School RuneScape player can make to speed up combat training. Unlike standard weapons that occupy your hands, this mechanical marvel sits on the floor, rotating and firing projectiles while you simultaneously attack with your primary weapon. It transforms slow, tedious Slayer tasks into high-speed experience farms. However, owning a cannon is one thing; understanding the complex mechanics behind its accuracy and positioning is what separates the average player from the efficiency expert.

Unlocking the Cannon: The Logistics of the Black Guard

Before you can deploy this weapon, you must complete the Dwarf Cannon quest. It is a short, novice-level quest located northwest of the Fishing Guild at the Black Guard outpost. The quest involves repairing railings, finding a lost child in a cave, and assisting Captain Lawgof with mechanical repairs. Upon completion, you gain the right to purchase and use the multicannon.

As of 2026, the cost remains a significant barrier for early-game players. Nulodian, located at the dwarven base south of Ice Mountain, sells the full set—base, stand, furnace, and barrels—for 750,000 coins through dialogue. Interestingly, buying individual parts via his trade screen costs 200,625 each, totaling 802,500 coins. Therefore, always use the dialogue option to save roughly 52,000 GP. If the Grand Exchange price is lower than 750k, buy it there, but usually, the set maintains a stable value near its NPC shop price.

The Misunderstood Mechanic: How Accuracy Actually Works

The single biggest misconception about the OSRS dwarf cannon is that its accuracy depends solely on your Ranged level. This is incorrect. The cannon's accuracy is determined by your highest current attack bonus.

If you are wearing full melee gear and wielding a Ghrazi Rapier on 'Stab' style, the cannon will use your Stab attack bonus to calculate its hit chance. If you switch to a Godsword on 'Crush', it uses your Crush bonus. This unique mechanic makes the cannon incredibly versatile. Melee-focused Slayer players can benefit from a cannon just as much as Ranged users. To maximize the cannon's DPS, you should wear gear with high offensive bonuses for whatever combat style you are currently using.

Furthermore, offensive prayers like Piety, Rigour, or Augury also boost the cannon’s accuracy because they increase your character's active attack bonuses. Even if you aren't actively attacking a monster, having a high-bonus weapon equipped while the cannon fires will result in fewer 'zeroes' and more consistent damage.

Ammunition and Damage Output

The cannon has two types of ammunition: standard Cannonballs and Granite Cannonballs.

  1. Standard Cannonballs: These have a static max hit of 30. They are the bread and butter of Slayer training. You can smith them yourself at level 35 Smithing using a steel bar and an ammo mould at a furnace, yielding four balls per bar.
  2. Granite Cannonballs: By using a hammer to combine granite dust (obtained from the Grotesque Guardians) with standard cannonballs, you create a variant with a max hit of 35. This 16.6% increase in damage is significant for speed-running tasks or high-level bossing, though the time required to gather the dust makes them less viable for general training unless you enjoy the Gargoyle boss fight.

The cannon rotates in a circle, checking for targets in eight directions. It fires a ball every time a monster is in its line of sight during its rotation tick. Each full revolution takes 4.8 seconds (8 game ticks). In a multicombat zone, if positioned correctly, the cannon can fire up to 8 times per revolution, leading to massive XP rates.

Advanced Positioning and the "Double Hit" Strategy

Strategic placement is the difference between mediocre and elite XP rates. The cannon occupies a 1x1 space but requires a 3x3 area to be set up. Most monsters in OSRS occupy more than one tile (2x2, 3x3, etc.). Because the cannon fires from its center point toward the target, certain placements allow the cannon to hit a large monster twice in a single rotation.

These "double-hit spots" occur when the monster's hitbox spans across two of the cannon's firing lines simultaneously. For example, when fighting Kalphites or Dagannoths, placing the cannon in specific tiles allows it to fire at the monster at the end of one 45-degree arc and the start of the next. This effectively doubles your cannon's DPS against that specific target. Always look for community-mapped "optimal cannon tiles" for specific Slayer dungeons to exploit this.

Combat Achievements and Quality of Life

Historically, the cannon could only hold 30 cannonballs before requiring a manual reload. This made it a click-intensive tool. However, the Combat Achievement system has introduced tiers of upgrades that significantly improve the experience.

Completing the Easy, Medium, Hard, and Elite tiers of Combat Achievements increases the cannon's capacity. At the Elite tier, the cannon can hold 60 balls. This doubles your "AFK" time, allowing you to focus on looting or managing your primary combat encounters without constantly clicking the cannon every 30 seconds. This upgrade is highly recommended for anyone planning to reach 99 Slayer.

The Southwest Tile Rule and Firing Delays

A common frustration occurs when a player loads a cannon and it doesn't immediately start firing. This is often linked to the player's position. If the cannon is empty and you load it while standing directly on or next to it, and then immediately move away, the game sometimes fails to register the "fire" command.

To reset or force the cannon to start firing, players often run to the "Southwest tile" relative to the cannon. This is a known pathing quirk in the OSRS engine. If your cannon is acting up, simply stepping to the tile immediately southwest of the base usually triggers the firing sequence.

Best Places to Use Your Cannon in 2026

While you can technically use the cannon in many places, it is most cost-effective in multicombat areas or against monsters with high HP and low defense. Here are the top locations for 2026:

  • Dagannoth Cave (Under the Lighthouse): Requires Horror from the Deep. This is the gold standard for cannoning. The Dagannoths are aggressive, low defense, and packed tightly. You can achieve over 100k Ranged XP per hour here easily.
  • Kalphite Hive: Use the task-only area for better spawns. Kalphite Soldiers and Guardians are perfect for double-hitting.
  • Shayzien Graveyard (Hill Giants): An underrated spot for mid-level players. The Hill Giants are weak, and the area is usually less crowded than the specialized Slayer dungeons.
  • Smoke Devil Dungeon: For high-level Slayer (level 93+), the cannon is mandatory here to stack the Thermonuclear Smoke Devil or the smaller variants for insane burst damage.
  • Scabarites: Located in the Sophanem Slayer Dungeon. They are extremely aggressive and provide excellent XP, though they can be dangerous without proper protection prayers.

Is the Investment Worth It?

The cost of using a cannon is high. Depending on current market rates, firing a cannon for an hour can cost anywhere from 150k to 300k GP in ammunition. Because the cannon only grants 2 XP per damage dealt (compared to 4 XP for manual Ranged attacks) and grants zero Hitpoints XP, it is technically an expensive way to train.

However, the time saved is where the value lies. By speeding up Slayer tasks, you reach high-level, profitable bosses (like Hydra, Cerberus, or Kraken) much faster. The GP you lose on cannonballs is often recouped by the high-value loot these bosses drop. In the modern meta, the cannon is not seen as a waste of money, but as a way to buy back your time.

Maintenance: What Happens if You Lose Your Cannon?

One of the most player-friendly aspects of the dwarf multicannon is its replacement policy. If your cannon is destroyed by a boss (like the King Black Dragon or the Corporeal Beast) or if you simply forget to pick it up and it decays after 25 minutes, you do not need to buy a new one.

Simply head back to Nulodian at the dwarven base. He will give you a replacement cannon for free. He even recovers any cannonballs that were loaded into the device when it was lost. The only way to truly "lose" the 750k investment is by dropping the parts manually or losing them in a PvP death above level 20 Wilderness (where they convert to coins for the killer).

Pro Tips for Efficiency

  • The Telekinetic Grab Pause: Be aware that casting Telekinetic Grab will momentarily pause the cannon's rotation. If you are using the spell to loot items from a distance, you are slightly lowering your DPS.
  • Single-Combat Safespotting: In single-combat zones, the cannon will only fire at the monster you are currently attacking. However, if you are in a safespot and no monster is currently "in combat" with you, the cannon will behave as if it's in a multi-zone and target multiple enemies until one of them manages to engage you.
  • Weight Management: Cannon parts are heavy (over 40kg total). If you are traveling long distances to a Slayer spot, consider using Stamina potions or wearing weight-reducing gear like Graceful until you reach your destination and set the device down.

The dwarf multicannon remains a cornerstone of the OSRS experience. Whether you are a casual player looking to get through a boring Greater Demon task or a hardcore efficientist chasing 200m XP, mastering this dwarven technology is essential. Keep your bonuses high, your ammo count higher, and your cannon will do the heavy lifting for you.