diff --git a/apps/essimporter/convertplayer.cpp b/apps/essimporter/convertplayer.cpp
index eeb1ecbc11..29c49451fd 100644
--- a/apps/essimporter/convertplayer.cpp
+++ b/apps/essimporter/convertplayer.cpp
@@ -25,11 +25,11 @@ namespace ESSImport
             faction.mReputation = essFaction.mReputation;
             out.mObject.mNpcStats.mFactions[ESM::RefId::stringRefId(essFaction.mFactionName.toString())] = faction;
         }
-        for (int i = 0; i < 3; ++i)
+        for (size_t i = 0; i < out.mObject.mNpcStats.mSpecIncreases.size(); ++i)
             out.mObject.mNpcStats.mSpecIncreases[i] = pcdt.mPNAM.mSpecIncreases[i];
-        for (int i = 0; i < 8; ++i)
+        for (size_t i = 0; i < out.mObject.mNpcStats.mSkillIncrease.size(); ++i)
             out.mObject.mNpcStats.mSkillIncrease[i] = pcdt.mPNAM.mSkillIncreases[i];
-        for (int i = 0; i < 27; ++i)
+        for (size_t i = 0; i < out.mObject.mNpcStats.mSkills.size(); ++i)
             out.mObject.mNpcStats.mSkills[i].mProgress = pcdt.mPNAM.mSkillProgress[i];
         out.mObject.mNpcStats.mLevelProgress = pcdt.mPNAM.mLevelProgress;
 
diff --git a/apps/openmw/mwmechanics/npcstats.cpp b/apps/openmw/mwmechanics/npcstats.cpp
index 242f87591c..e9812e7931 100644
--- a/apps/openmw/mwmechanics/npcstats.cpp
+++ b/apps/openmw/mwmechanics/npcstats.cpp
@@ -470,7 +470,7 @@ void MWMechanics::NpcStats::writeState(ESM::NpcStats& state) const
 
     state.mDisposition = mDisposition;
 
-    for (int i = 0; i < ESM::Skill::Length; ++i)
+    for (size_t i = 0; i < state.mSkills.size(); ++i)
         mSkill[i].writeState(state.mSkills[i]);
 
     state.mIsWerewolf = mIsWerewolf;
@@ -489,10 +489,10 @@ void MWMechanics::NpcStats::writeState(ESM::NpcStats& state) const
     state.mWerewolfKills = mWerewolfKills;
     state.mLevelProgress = mLevelProgress;
 
-    for (int i = 0; i < ESM::Attribute::Length; ++i)
+    for (size_t i = 0; i < state.mSkillIncrease.size(); ++i)
         state.mSkillIncrease[i] = mSkillIncreases[i];
 
-    for (int i = 0; i < 3; ++i)
+    for (size_t i = 0; i < state.mSpecIncreases.size(); ++i)
         state.mSpecIncreases[i] = mSpecIncreases[i];
 
     std::copy(mUsedIds.begin(), mUsedIds.end(), std::back_inserter(state.mUsedIds));
@@ -523,7 +523,7 @@ void MWMechanics::NpcStats::readState(const ESM::NpcStats& state)
 
     mDisposition = state.mDisposition;
 
-    for (int i = 0; i < ESM::Skill::Length; ++i)
+    for (size_t i = 0; i < state.mSkills.size(); ++i)
         mSkill[i].readState(state.mSkills[i]);
 
     mIsWerewolf = state.mIsWerewolf;
@@ -534,10 +534,10 @@ void MWMechanics::NpcStats::readState(const ESM::NpcStats& state)
     mWerewolfKills = state.mWerewolfKills;
     mLevelProgress = state.mLevelProgress;
 
-    for (int i = 0; i < ESM::Attribute::Length; ++i)
+    for (size_t i = 0; i < state.mSkillIncrease.size(); ++i)
         mSkillIncreases[i] = state.mSkillIncrease[i];
 
-    for (int i = 0; i < 3; ++i)
+    for (size_t i = 0; i < state.mSpecIncreases.size(); ++i)
         mSpecIncreases[i] = state.mSpecIncreases[i];
 
     for (auto iter(state.mUsedIds.begin()); iter != state.mUsedIds.end(); ++iter)
diff --git a/components/esm3/npcstats.cpp b/components/esm3/npcstats.cpp
index 0f271556bb..e2ee4f50d4 100644
--- a/components/esm3/npcstats.cpp
+++ b/components/esm3/npcstats.cpp
@@ -31,15 +31,15 @@ namespace ESM
 
             esm.getHNOT(faction.mReputation, "FARE");
 
-            mFactions.insert(std::make_pair(id, faction));
+            mFactions.emplace(id, faction);
         }
 
         mDisposition = 0;
         esm.getHNOT(mDisposition, "DISP");
 
         const bool intFallback = esm.getFormatVersion() <= MaxIntFallbackFormatVersion;
-        for (int i = 0; i < 27; ++i)
-            mSkills[i].load(esm, intFallback);
+        for (auto& skill : mSkills)
+            skill.load(esm, intFallback);
 
         mWerewolfDeprecatedData = false;
         if (esm.getFormatVersion() <= MaxWerewolfDeprecatedDataFormatVersion && esm.peekNextSub("STBA"))
@@ -47,9 +47,9 @@ namespace ESM
             // we have deprecated werewolf skills, stored interleaved
             // Load into one big vector, then remove every 2nd value
             mWerewolfDeprecatedData = true;
-            std::vector<StatState<float>> skills(mSkills, mSkills + sizeof(mSkills) / sizeof(mSkills[0]));
+            std::vector<StatState<float>> skills(mSkills.begin(), mSkills.end());
 
-            for (int i = 0; i < 27; ++i)
+            for (int i = 0; i < ESM::Skill::Length; ++i)
             {
                 StatState<float> skill;
                 skill.load(esm, intFallback);
@@ -67,7 +67,7 @@ namespace ESM
             if (skills.size() != std::size(mSkills))
                 throw std::runtime_error(
                     "Invalid number of skill for werewolf deprecated data: " + std::to_string(skills.size()));
-            std::copy(skills.begin(), skills.end(), mSkills);
+            std::copy(skills.begin(), skills.end(), mSkills.begin());
         }
 
         // No longer used
@@ -76,7 +76,7 @@ namespace ESM
         if (hasWerewolfAttributes)
         {
             StatState<int> dummy;
-            for (int i = 0; i < 8; ++i)
+            for (int i = 0; i < ESM::Attribute::Length; ++i)
                 dummy.load(esm, intFallback);
             mWerewolfDeprecatedData = true;
         }
@@ -104,12 +104,10 @@ namespace ESM
         mLevelProgress = 0;
         esm.getHNOT(mLevelProgress, "LPRO");
 
-        for (int i = 0; i < 8; ++i)
-            mSkillIncrease[i] = 0;
+        mSkillIncrease.fill(0);
         esm.getHNOT(mSkillIncrease, "INCR");
 
-        for (int i = 0; i < 3; ++i)
-            mSpecIncreases[i] = 0;
+        mSpecIncreases.fill(0);
         esm.getHNOT(mSpecIncreases, "SPEC");
 
         while (esm.isNextSub("USED"))
@@ -152,8 +150,8 @@ namespace ESM
         if (mDisposition)
             esm.writeHNT("DISP", mDisposition);
 
-        for (int i = 0; i < 27; ++i)
-            mSkills[i].save(esm);
+        for (const auto& skill : mSkills)
+            skill.save(esm);
 
         if (mIsWerewolf)
             esm.writeHNT("WOLF", mIsWerewolf);
@@ -171,9 +169,9 @@ namespace ESM
             esm.writeHNT("LPRO", mLevelProgress);
 
         bool saveSkillIncreases = false;
-        for (int i = 0; i < 8; ++i)
+        for (int increase : mSkillIncrease)
         {
-            if (mSkillIncrease[i] != 0)
+            if (increase != 0)
             {
                 saveSkillIncreases = true;
                 break;
@@ -204,10 +202,8 @@ namespace ESM
         mReputation = 0;
         mWerewolfKills = 0;
         mLevelProgress = 0;
-        for (int i = 0; i < 8; ++i)
-            mSkillIncrease[i] = 0;
-        for (int i = 0; i < 3; ++i)
-            mSpecIncreases[i] = 0;
+        mSkillIncrease.fill(0);
+        mSpecIncreases.fill(0);
         mTimeToStartDrowning = 20;
         mCrimeId = -1;
     }
diff --git a/components/esm3/npcstats.hpp b/components/esm3/npcstats.hpp
index b9e2e6bb9b..e80ec04c25 100644
--- a/components/esm3/npcstats.hpp
+++ b/components/esm3/npcstats.hpp
@@ -1,8 +1,12 @@
 #ifndef OPENMW_ESM_NPCSTATS_H
 #define OPENMW_ESM_NPCSTATS_H
 
+#include "loadskil.hpp"
 #include "statstate.hpp"
+#include <components/esm/attr.hpp>
 #include <components/esm/refid.hpp>
+
+#include <array>
 #include <map>
 #include <string>
 #include <vector>
@@ -31,13 +35,13 @@ namespace ESM
 
         std::map<ESM::RefId, Faction> mFactions; // lower case IDs
         int mDisposition;
-        StatState<float> mSkills[27];
+        std::array<StatState<float>, ESM::Skill::Length> mSkills;
         int mBounty;
         int mReputation;
         int mWerewolfKills;
         int mLevelProgress;
-        int mSkillIncrease[8];
-        int mSpecIncreases[3];
+        std::array<int, ESM::Attribute::Length> mSkillIncrease;
+        std::array<int, 3> mSpecIncreases;
         std::vector<ESM::RefId> mUsedIds; // lower case IDs
         float mTimeToStartDrowning;
         int mCrimeId;