diff --git a/osu.Game.Rulesets.Catch/CatchRuleset.cs b/osu.Game.Rulesets.Catch/CatchRuleset.cs
index 15e51fa126..2325a8cad9 100644
--- a/osu.Game.Rulesets.Catch/CatchRuleset.cs
+++ b/osu.Game.Rulesets.Catch/CatchRuleset.cs
@@ -14,6 +14,8 @@ using osu.Game.Rulesets.Catch.Replays;
 using osu.Game.Rulesets.Replays.Types;
 using osu.Game.Beatmaps.Legacy;
 using osu.Game.Rulesets.Catch.Beatmaps;
+using osu.Game.Rulesets.Catch.Difficulty;
+using osu.Game.Rulesets.Difficulty;
 
 namespace osu.Game.Rulesets.Catch
 {
diff --git a/osu.Game.Rulesets.Catch/CatchDifficultyCalculator.cs b/osu.Game.Rulesets.Catch/Difficulty/CatchDifficultyCalculator.cs
similarity index 85%
rename from osu.Game.Rulesets.Catch/CatchDifficultyCalculator.cs
rename to osu.Game.Rulesets.Catch/Difficulty/CatchDifficultyCalculator.cs
index f47d09fe20..f8351b7519 100644
--- a/osu.Game.Rulesets.Catch/CatchDifficultyCalculator.cs
+++ b/osu.Game.Rulesets.Catch/Difficulty/CatchDifficultyCalculator.cs
@@ -1,10 +1,11 @@
 // Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
-using osu.Game.Beatmaps;
 using System.Collections.Generic;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Difficulty;
 
-namespace osu.Game.Rulesets.Catch
+namespace osu.Game.Rulesets.Catch.Difficulty
 {
     public class CatchDifficultyCalculator : DifficultyCalculator
     {
diff --git a/osu.Game.Rulesets.Mania/ManiaDifficultyCalculator.cs b/osu.Game.Rulesets.Mania/Difficulty/ManiaDifficultyCalculator.cs
similarity index 98%
rename from osu.Game.Rulesets.Mania/ManiaDifficultyCalculator.cs
rename to osu.Game.Rulesets.Mania/Difficulty/ManiaDifficultyCalculator.cs
index 822ba53eeb..ac45130fd8 100644
--- a/osu.Game.Rulesets.Mania/ManiaDifficultyCalculator.cs
+++ b/osu.Game.Rulesets.Mania/Difficulty/ManiaDifficultyCalculator.cs
@@ -1,14 +1,15 @@
 // Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
+using System;
+using System.Collections.Generic;
 using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Difficulty;
 using osu.Game.Rulesets.Mania.Beatmaps;
 using osu.Game.Rulesets.Mania.Objects;
 using osu.Game.Rulesets.Mods;
-using System;
-using System.Collections.Generic;
 
-namespace osu.Game.Rulesets.Mania
+namespace osu.Game.Rulesets.Mania.Difficulty
 {
     internal class ManiaDifficultyCalculator : DifficultyCalculator
     {
diff --git a/osu.Game.Rulesets.Mania/ManiaRuleset.cs b/osu.Game.Rulesets.Mania/ManiaRuleset.cs
index f1d65f855b..b1702de537 100644
--- a/osu.Game.Rulesets.Mania/ManiaRuleset.cs
+++ b/osu.Game.Rulesets.Mania/ManiaRuleset.cs
@@ -15,7 +15,9 @@ using osu.Game.Graphics;
 using osu.Game.Rulesets.Mania.Replays;
 using osu.Game.Rulesets.Replays.Types;
 using osu.Game.Beatmaps.Legacy;
+using osu.Game.Rulesets.Difficulty;
 using osu.Game.Rulesets.Mania.Beatmaps;
+using osu.Game.Rulesets.Mania.Difficulty;
 
 namespace osu.Game.Rulesets.Mania
 {
diff --git a/osu.Game.Rulesets.Osu/OsuDifficulty/OsuDifficultyCalculator.cs b/osu.Game.Rulesets.Osu/Difficulty/OsuDifficultyCalculator.cs
similarity index 92%
rename from osu.Game.Rulesets.Osu/OsuDifficulty/OsuDifficultyCalculator.cs
rename to osu.Game.Rulesets.Osu/Difficulty/OsuDifficultyCalculator.cs
index 4853cd66cd..bd8d18af41 100644
--- a/osu.Game.Rulesets.Osu/OsuDifficulty/OsuDifficultyCalculator.cs
+++ b/osu.Game.Rulesets.Osu/Difficulty/OsuDifficultyCalculator.cs
@@ -4,12 +4,13 @@
 using System;
 using System.Collections.Generic;
 using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Difficulty;
 using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.Osu.Difficulty.Preprocessing;
+using osu.Game.Rulesets.Osu.Difficulty.Skills;
 using osu.Game.Rulesets.Osu.Objects;
-using osu.Game.Rulesets.Osu.OsuDifficulty.Preprocessing;
-using osu.Game.Rulesets.Osu.OsuDifficulty.Skills;
 
-namespace osu.Game.Rulesets.Osu.OsuDifficulty
+namespace osu.Game.Rulesets.Osu.Difficulty
 {
     public class OsuDifficultyCalculator : DifficultyCalculator
     {
diff --git a/osu.Game.Rulesets.Osu/OsuDifficulty/Preprocessing/OsuDifficultyBeatmap.cs b/osu.Game.Rulesets.Osu/Difficulty/Preprocessing/OsuDifficultyBeatmap.cs
similarity index 98%
rename from osu.Game.Rulesets.Osu/OsuDifficulty/Preprocessing/OsuDifficultyBeatmap.cs
rename to osu.Game.Rulesets.Osu/Difficulty/Preprocessing/OsuDifficultyBeatmap.cs
index 5c8ab0f3d4..e97042a9aa 100644
--- a/osu.Game.Rulesets.Osu/OsuDifficulty/Preprocessing/OsuDifficultyBeatmap.cs
+++ b/osu.Game.Rulesets.Osu/Difficulty/Preprocessing/OsuDifficultyBeatmap.cs
@@ -5,7 +5,7 @@ using System.Collections;
 using System.Collections.Generic;
 using osu.Game.Rulesets.Osu.Objects;
 
-namespace osu.Game.Rulesets.Osu.OsuDifficulty.Preprocessing
+namespace osu.Game.Rulesets.Osu.Difficulty.Preprocessing
 {
     /// <summary>
     /// An enumerable container wrapping <see cref="OsuHitObject"/> input as <see cref="OsuDifficultyHitObject"/>
diff --git a/osu.Game.Rulesets.Osu/OsuDifficulty/Preprocessing/OsuDifficultyHitObject.cs b/osu.Game.Rulesets.Osu/Difficulty/Preprocessing/OsuDifficultyHitObject.cs
similarity index 98%
rename from osu.Game.Rulesets.Osu/OsuDifficulty/Preprocessing/OsuDifficultyHitObject.cs
rename to osu.Game.Rulesets.Osu/Difficulty/Preprocessing/OsuDifficultyHitObject.cs
index 415f76ced8..f95426466b 100644
--- a/osu.Game.Rulesets.Osu/OsuDifficulty/Preprocessing/OsuDifficultyHitObject.cs
+++ b/osu.Game.Rulesets.Osu/Difficulty/Preprocessing/OsuDifficultyHitObject.cs
@@ -3,10 +3,10 @@
 
 using System;
 using System.Linq;
-using OpenTK;
 using osu.Game.Rulesets.Osu.Objects;
+using OpenTK;
 
-namespace osu.Game.Rulesets.Osu.OsuDifficulty.Preprocessing
+namespace osu.Game.Rulesets.Osu.Difficulty.Preprocessing
 {
     /// <summary>
     /// A wrapper around <see cref="OsuHitObject"/> extending it with additional data required for difficulty calculation.
diff --git a/osu.Game.Rulesets.Osu/OsuDifficulty/Skills/Aim.cs b/osu.Game.Rulesets.Osu/Difficulty/Skills/Aim.cs
similarity index 85%
rename from osu.Game.Rulesets.Osu/OsuDifficulty/Skills/Aim.cs
rename to osu.Game.Rulesets.Osu/Difficulty/Skills/Aim.cs
index 5c736d7bb5..0a45c62671 100644
--- a/osu.Game.Rulesets.Osu/OsuDifficulty/Skills/Aim.cs
+++ b/osu.Game.Rulesets.Osu/Difficulty/Skills/Aim.cs
@@ -2,9 +2,9 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using System;
-using osu.Game.Rulesets.Osu.OsuDifficulty.Preprocessing;
+using osu.Game.Rulesets.Osu.Difficulty.Preprocessing;
 
-namespace osu.Game.Rulesets.Osu.OsuDifficulty.Skills
+namespace osu.Game.Rulesets.Osu.Difficulty.Skills
 {
     /// <summary>
     /// Represents the skill required to correctly aim at every object in the map with a uniform CircleSize and normalized distances.
diff --git a/osu.Game.Rulesets.Osu/OsuDifficulty/Skills/Skill.cs b/osu.Game.Rulesets.Osu/Difficulty/Skills/Skill.cs
similarity index 96%
rename from osu.Game.Rulesets.Osu/OsuDifficulty/Skills/Skill.cs
rename to osu.Game.Rulesets.Osu/Difficulty/Skills/Skill.cs
index 983599432f..47037c1503 100644
--- a/osu.Game.Rulesets.Osu/OsuDifficulty/Skills/Skill.cs
+++ b/osu.Game.Rulesets.Osu/Difficulty/Skills/Skill.cs
@@ -3,11 +3,11 @@
 
 using System;
 using System.Collections.Generic;
+using osu.Game.Rulesets.Osu.Difficulty.Preprocessing;
+using osu.Game.Rulesets.Osu.Difficulty.Utils;
 using osu.Game.Rulesets.Osu.Objects;
-using osu.Game.Rulesets.Osu.OsuDifficulty.Preprocessing;
-using osu.Game.Rulesets.Osu.OsuDifficulty.Utils;
 
-namespace osu.Game.Rulesets.Osu.OsuDifficulty.Skills
+namespace osu.Game.Rulesets.Osu.Difficulty.Skills
 {
     /// <summary>
     /// Used to processes strain values of <see cref="OsuDifficultyHitObject"/>s, keep track of strain levels caused by the processed objects
diff --git a/osu.Game.Rulesets.Osu/OsuDifficulty/Skills/Speed.cs b/osu.Game.Rulesets.Osu/Difficulty/Skills/Speed.cs
similarity index 93%
rename from osu.Game.Rulesets.Osu/OsuDifficulty/Skills/Speed.cs
rename to osu.Game.Rulesets.Osu/Difficulty/Skills/Speed.cs
index ae3caa1e66..b807f20037 100644
--- a/osu.Game.Rulesets.Osu/OsuDifficulty/Skills/Speed.cs
+++ b/osu.Game.Rulesets.Osu/Difficulty/Skills/Speed.cs
@@ -1,9 +1,9 @@
 // Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
-using osu.Game.Rulesets.Osu.OsuDifficulty.Preprocessing;
+using osu.Game.Rulesets.Osu.Difficulty.Preprocessing;
 
-namespace osu.Game.Rulesets.Osu.OsuDifficulty.Skills
+namespace osu.Game.Rulesets.Osu.Difficulty.Skills
 {
     /// <summary>
     /// Represents the skill required to press keys with regards to keeping up with the speed at which objects need to be hit.
diff --git a/osu.Game.Rulesets.Osu/OsuDifficulty/Utils/History.cs b/osu.Game.Rulesets.Osu/Difficulty/Utils/History.cs
similarity index 98%
rename from osu.Game.Rulesets.Osu/OsuDifficulty/Utils/History.cs
rename to osu.Game.Rulesets.Osu/Difficulty/Utils/History.cs
index f6933a3e5d..55bd950209 100644
--- a/osu.Game.Rulesets.Osu/OsuDifficulty/Utils/History.cs
+++ b/osu.Game.Rulesets.Osu/Difficulty/Utils/History.cs
@@ -5,7 +5,7 @@ using System;
 using System.Collections;
 using System.Collections.Generic;
 
-namespace osu.Game.Rulesets.Osu.OsuDifficulty.Utils
+namespace osu.Game.Rulesets.Osu.Difficulty.Utils
 {
     /// <summary>
     /// An indexed stack with Push() only, which disposes items at the bottom after the capacity is full.
diff --git a/osu.Game.Rulesets.Osu/OsuRuleset.cs b/osu.Game.Rulesets.Osu/OsuRuleset.cs
index 69a54fb533..a2423ffbe5 100644
--- a/osu.Game.Rulesets.Osu/OsuRuleset.cs
+++ b/osu.Game.Rulesets.Osu/OsuRuleset.cs
@@ -5,7 +5,6 @@ using osu.Game.Beatmaps;
 using osu.Game.Graphics;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Osu.Mods;
-using osu.Game.Rulesets.Osu.OsuDifficulty;
 using osu.Game.Rulesets.Osu.UI;
 using osu.Game.Rulesets.UI;
 using System.Collections.Generic;
@@ -19,7 +18,9 @@ using osu.Game.Rulesets.Edit;
 using osu.Game.Rulesets.Osu.Replays;
 using osu.Game.Rulesets.Replays.Types;
 using osu.Game.Beatmaps.Legacy;
+using osu.Game.Rulesets.Difficulty;
 using osu.Game.Rulesets.Osu.Beatmaps;
+using osu.Game.Rulesets.Osu.Difficulty;
 
 namespace osu.Game.Rulesets.Osu
 {
diff --git a/osu.Game.Rulesets.Osu/Scoring/OsuPerformanceCalculator.cs b/osu.Game.Rulesets.Osu/Scoring/OsuPerformanceCalculator.cs
index 793060197d..938060a664 100644
--- a/osu.Game.Rulesets.Osu/Scoring/OsuPerformanceCalculator.cs
+++ b/osu.Game.Rulesets.Osu/Scoring/OsuPerformanceCalculator.cs
@@ -5,6 +5,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Difficulty;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Osu.Mods;
 using osu.Game.Rulesets.Osu.Objects;
diff --git a/osu.Game.Rulesets.Taiko/TaikoDifficultyCalculator.cs b/osu.Game.Rulesets.Taiko/Difficulty/TaikoDifficultyCalculator.cs
similarity index 98%
rename from osu.Game.Rulesets.Taiko/TaikoDifficultyCalculator.cs
rename to osu.Game.Rulesets.Taiko/Difficulty/TaikoDifficultyCalculator.cs
index f14c53f7ae..acff0d286d 100644
--- a/osu.Game.Rulesets.Taiko/TaikoDifficultyCalculator.cs
+++ b/osu.Game.Rulesets.Taiko/Difficulty/TaikoDifficultyCalculator.cs
@@ -1,12 +1,13 @@
 // Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
-using osu.Game.Beatmaps;
-using osu.Game.Rulesets.Taiko.Objects;
-using System.Collections.Generic;
 using System;
+using System.Collections.Generic;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Difficulty;
+using osu.Game.Rulesets.Taiko.Objects;
 
-namespace osu.Game.Rulesets.Taiko
+namespace osu.Game.Rulesets.Taiko.Difficulty
 {
     internal class TaikoDifficultyCalculator : DifficultyCalculator
     {
diff --git a/osu.Game.Rulesets.Taiko/TaikoRuleset.cs b/osu.Game.Rulesets.Taiko/TaikoRuleset.cs
index 102de5717f..35dc17c0e2 100644
--- a/osu.Game.Rulesets.Taiko/TaikoRuleset.cs
+++ b/osu.Game.Rulesets.Taiko/TaikoRuleset.cs
@@ -13,7 +13,9 @@ using osu.Framework.Input.Bindings;
 using osu.Game.Rulesets.Replays.Types;
 using osu.Game.Rulesets.Taiko.Replays;
 using osu.Game.Beatmaps.Legacy;
+using osu.Game.Rulesets.Difficulty;
 using osu.Game.Rulesets.Taiko.Beatmaps;
+using osu.Game.Rulesets.Taiko.Difficulty;
 
 namespace osu.Game.Rulesets.Taiko
 {
diff --git a/osu.Game/Beatmaps/DummyWorkingBeatmap.cs b/osu.Game/Beatmaps/DummyWorkingBeatmap.cs
index da52dc7284..8094abe5ed 100644
--- a/osu.Game/Beatmaps/DummyWorkingBeatmap.cs
+++ b/osu.Game/Beatmaps/DummyWorkingBeatmap.cs
@@ -6,6 +6,7 @@ using System.Collections.Generic;
 using osu.Framework.Audio.Track;
 using osu.Framework.Graphics.Textures;
 using osu.Game.Rulesets;
+using osu.Game.Rulesets.Difficulty;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.UI;
diff --git a/osu.Game/Beatmaps/DifficultyCalculator.cs b/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
similarity index 94%
rename from osu.Game/Beatmaps/DifficultyCalculator.cs
rename to osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
index 5cac9ed923..070bc7ddb0 100644
--- a/osu.Game/Beatmaps/DifficultyCalculator.cs
+++ b/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
@@ -2,12 +2,13 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using System.Collections.Generic;
-using osu.Game.Rulesets.Mods;
-using osu.Framework.Timing;
 using System.Linq;
 using osu.Framework.Extensions.IEnumerableExtensions;
+using osu.Framework.Timing;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Mods;
 
-namespace osu.Game.Beatmaps
+namespace osu.Game.Rulesets.Difficulty
 {
     public abstract class DifficultyCalculator
     {
diff --git a/osu.Game/Rulesets/Scoring/PerformanceCalculator.cs b/osu.Game/Rulesets/Difficulty/PerformanceCalculator.cs
similarity index 95%
rename from osu.Game/Rulesets/Scoring/PerformanceCalculator.cs
rename to osu.Game/Rulesets/Difficulty/PerformanceCalculator.cs
index f2c495fa5d..9fd7a0156d 100644
--- a/osu.Game/Rulesets/Scoring/PerformanceCalculator.cs
+++ b/osu.Game/Rulesets/Difficulty/PerformanceCalculator.cs
@@ -7,8 +7,9 @@ using osu.Framework.Extensions.IEnumerableExtensions;
 using osu.Framework.Timing;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.Scoring;
 
-namespace osu.Game.Rulesets.Scoring
+namespace osu.Game.Rulesets.Difficulty
 {
     public abstract class PerformanceCalculator
     {
diff --git a/osu.Game/Rulesets/Ruleset.cs b/osu.Game/Rulesets/Ruleset.cs
index 6883d319f4..395eeab419 100644
--- a/osu.Game/Rulesets/Ruleset.cs
+++ b/osu.Game/Rulesets/Ruleset.cs
@@ -15,6 +15,7 @@ using osu.Game.Rulesets.Replays.Types;
 using osu.Game.Rulesets.Scoring;
 using osu.Game.Rulesets.UI;
 using osu.Game.Beatmaps.Legacy;
+using osu.Game.Rulesets.Difficulty;
 
 namespace osu.Game.Rulesets
 {