Scripting and Extensions/Combat Simulator

Combat Simulator is a mod that can be used to simulate many Combat scenarios such as fights against particular Monsters, Slayer tasks, or dungeon clears with a loadout (equipment set, levels, pets, prayers, etc.) of the user's choice. Each simulation produces various metrics, allowing the user to determine things such as:

  • If monsters or dungeons can be safely idled
  • Optimal loadouts for maximizing XP rates, GP rates, drop rates, or dungeon clear rates
  • Which monster provides the highest XP rates with a given loadout
This page is up to date (v1.2.2).

The Combat Simulator can also give necessary data to calculate an important metric - the Adjusted Clear Time, being the time taken to clear a dungeon inclusive of time taken to gather all resources necessary to achieve that dungeon clear. The production of food and ammunition might take more time than the encounter itself, which can lead to interesting outcomes such as a Melee build that clears a dungeon twice as slow but can still have better Adjusted Clear Time than a Magic build that consumes a lot of Food. An example of calculating this metric can be found in the Adjusted Clear Time section of the Dragons Den guide.


Question: The result says "No valid simulation data: simulated X/1000 trials". How do I fix this?

Answer: It means that due to the set limit, the program was only able to simulate X trials out of 1000 in this time limit. In order to increase the time limit, click on the gear icon on the upper right side and increase the value of the "Max ticks" parameter.

Question: How do I check how many loot I receive from a monster in a given hour?

  1. Open the Combat Simulator and navigate to the "Loot Options" tab. It looks like " ".
  2. Under "Choose Item" search and select the item that you require.
  3. Under the monster summary (the right-side panel) you should now see that Drops/h has changed to the selected item. For instance Feathers/h. This is the amount of (in this case) feathers you will receive in one hour of combat with the selected monster.
  4. Click "Simulate Selected" to see the results.

In case you want to search for a drop across various monsters (to select the best monster available) follow these steps:

  1. Open the Combat Simulator and navigate to the "Loot Options" tab. It looks like " ".
  2. Set "Only Selected Monster" to "No".
  3. Under "Choose Item" search and select the item that you require.
  4. Scroll down to "PlotType" on the bottom left side.
  5. In the left-most dropdown menu, select "Drops per"
  6. Click "Simulate all" to see the results. The results will show up in the graph at the bottom.

Question: I loaded the simulator like in the instructions, but there's no Tools section and no Combat Simulator button anywhere else. Am I doing something wrong?

Answer: It's likely because the Combat Simulator hasn't yet been updated for the most recent game version. The latest available version and changelog can be viewed via the in-game mod manager or from