diff --git a/lib/callback/CGameInfoCallback.cpp b/lib/callback/CGameInfoCallback.cpp
index b79612d26..07988d86e 100644
--- a/lib/callback/CGameInfoCallback.cpp
+++ b/lib/callback/CGameInfoCallback.cpp
@@ -574,7 +574,7 @@ EDiggingStatus CGameInfoCallback::getTileDigStatus(int3 tile, bool verbose) cons
 	return getTile(tile)->getDiggingStatus();
 }
 
-EBuildingState CGameInfoCallback::canBuildStructure( const CGTownInstance *t, BuildingID ID )
+EBuildingState CGameInfoCallback::canBuildStructure( const CGTownInstance *t, BuildingID ID ) const
 {
 	ERROR_RET_VAL_IF(!canGetFullInfo(t), "Town is not owned!", EBuildingState::TOWN_NOT_OWNED);
 
@@ -947,7 +947,7 @@ void CGameInfoCallback::getAllTiles(std::unordered_set<int3> & tiles, std::optio
 	}
 }
 
-void CGameInfoCallback::getAllowedSpells(std::vector<SpellID> & out, std::optional<ui16> level)
+void CGameInfoCallback::getAllowedSpells(std::vector<SpellID> & out, std::optional<ui16> level) const
 {
 	for (auto const & spellID : gameState().getMap().allowedSpells)
 	{
diff --git a/lib/callback/CGameInfoCallback.h b/lib/callback/CGameInfoCallback.h
index d9f31b287..a9fbddc91 100644
--- a/lib/callback/CGameInfoCallback.h
+++ b/lib/callback/CGameInfoCallback.h
@@ -93,7 +93,7 @@ public:
 	int howManyTowns(PlayerColor Player) const;
 	std::vector<const CGHeroInstance *> getAvailableHeroes(const CGObjectInstance * townOrTavern) const;
 	std::string getTavernRumor(const CGObjectInstance * townOrTavern) const;
-	EBuildingState canBuildStructure(const CGTownInstance *t, BuildingID ID);
+	EBuildingState canBuildStructure(const CGTownInstance *t, BuildingID ID) const;
 	bool getTownInfo(const CGObjectInstance * town, InfoAboutTown & dest, const CGObjectInstance * selectedObject = nullptr) const;
 
 	//from gs
@@ -115,7 +115,7 @@ public:
 	void getTilesInRange(std::unordered_set<int3> & tiles, const int3 & pos, int radius, ETileVisibility mode, std::optional<PlayerColor> player = std::optional<PlayerColor>(), int3::EDistanceFormula formula = int3::DIST_2D) const override;
 	void getAllTiles(std::unordered_set<int3> &tiles, std::optional<PlayerColor> player, int level, std::function<bool(const TerrainTile *)> filter) const override;
 
-	void getAllowedSpells(std::vector<SpellID> &out, std::optional<ui16> level = std::nullopt);
+	void getAllowedSpells(std::vector<SpellID> &out, std::optional<ui16> level = std::nullopt) const;
 
 #if SCRIPTING_ENABLED
 	virtual scripting::Pool * getGlobalContextPool() const override;
diff --git a/lib/gameState/CGameState.cpp b/lib/gameState/CGameState.cpp
index e2e75f7e3..7381d9cc4 100644
--- a/lib/gameState/CGameState.cpp
+++ b/lib/gameState/CGameState.cpp
@@ -1028,7 +1028,7 @@ BattleInfo * CGameState::getBattle(const BattleID & battle)
 	return nullptr;
 }
 
-BattleField CGameState::battleGetBattlefieldType(int3 tile, vstd::RNG & randomGenerator)
+BattleField CGameState::battleGetBattlefieldType(int3 tile, vstd::RNG & randomGenerator) const
 {
 	assert(tile.isValid());
 
@@ -1394,7 +1394,7 @@ bool CGameState::checkForStandardLoss(const PlayerColor & player) const
 	return pState.checkVanquished();
 }
 
-void CGameState::obtainPlayersStats(SThievesGuildInfo & tgi, int level)
+void CGameState::obtainPlayersStats(SThievesGuildInfo & tgi, int level) const
 {
 	auto playerInactive = [&](const PlayerColor & color) 
 	{
diff --git a/lib/gameState/CGameState.h b/lib/gameState/CGameState.h
index abc033290..71601f9e1 100644
--- a/lib/gameState/CGameState.h
+++ b/lib/gameState/CGameState.h
@@ -95,7 +95,7 @@ public:
 	HeroTypeID pickNextHeroType(vstd::RNG & randomGenerator, const PlayerColor & owner);
 
 	void apply(CPackForClient & pack);
-	BattleField battleGetBattlefieldType(int3 tile, vstd::RNG & randomGenerator);
+	BattleField battleGetBattlefieldType(int3 tile, vstd::RNG & randomGenerator) const;
 
 	PlayerRelations getPlayerRelations(PlayerColor color1, PlayerColor color2) const override;
 	void calculatePaths(const std::shared_ptr<PathfinderConfig> & config) const override;
@@ -123,7 +123,8 @@ public:
 	PlayerColor checkForStandardWin() const; //returns color of player that accomplished standard victory conditions or 255 (NEUTRAL) if no winner
 	bool checkForStandardLoss(const PlayerColor & player) const; //checks if given player lost the game
 
-	void obtainPlayersStats(SThievesGuildInfo & tgi, int level); //fills tgi with info about other players that is available at given level of thieves' guild
+	//fills tgi with info about other players that is available at given level of thieves' guild
+	void obtainPlayersStats(SThievesGuildInfo & tgi, int level) const;
 	const IGameSettings & getSettings() const override;
 
 	StartInfo * getStartInfo()
diff --git a/lib/gameState/GameStatistics.cpp b/lib/gameState/GameStatistics.cpp
index 4fc84edd0..87d24fa89 100644
--- a/lib/gameState/GameStatistics.cpp
+++ b/lib/gameState/GameStatistics.cpp
@@ -79,7 +79,7 @@ StatisticDataSetEntry StatisticDataSet::createEntry(const PlayerState * ps, cons
 	return data;
 }
 
-std::string StatisticDataSet::toCsv(std::string sep)
+std::string StatisticDataSet::toCsv(std::string sep) const
 {
 	std::stringstream ss;
 
@@ -162,7 +162,7 @@ std::string StatisticDataSet::toCsv(std::string sep)
 		for(auto & resource : resources)
 			ss << sep << entry.resources[resource];
 		for(auto & resource : resources)
-			ss << sep << entry.numMines[resource];
+			ss << sep << entry.numMines.at(resource);
 		for(auto & resource : resources)
 			ss << sep << entry.spentResourcesForArmy[resource];
 		for(auto & resource : resources)
@@ -175,7 +175,7 @@ std::string StatisticDataSet::toCsv(std::string sep)
 	return ss.str();
 }
 
-std::string StatisticDataSet::writeCsv()
+std::string StatisticDataSet::writeCsv() const
 {
 	const boost::filesystem::path outPath = VCMIDirs::get().userCachePath() / "statistic";
 	boost::filesystem::create_directories(outPath);
diff --git a/lib/gameState/GameStatistics.h b/lib/gameState/GameStatistics.h
index d8626cfc5..67bad5282 100644
--- a/lib/gameState/GameStatistics.h
+++ b/lib/gameState/GameStatistics.h
@@ -102,8 +102,8 @@ class DLL_LINKAGE StatisticDataSet
 public:
     void add(StatisticDataSetEntry entry);
 	static StatisticDataSetEntry createEntry(const PlayerState * ps, const CGameState * gs);
-    std::string toCsv(std::string sep);
-    std::string writeCsv();
+	std::string toCsv(std::string sep) const;
+	std::string writeCsv() const;
 
 	struct PlayerAccumulatedValueStorage // holds some actual values needed for stats
 	{
diff --git a/lib/mapping/CMap.cpp b/lib/mapping/CMap.cpp
index 29c71def3..d215419e7 100644
--- a/lib/mapping/CMap.cpp
+++ b/lib/mapping/CMap.cpp
@@ -868,12 +868,12 @@ const CArtifactInstance * CMap::getArtifactInstance(const ArtifactInstanceID & a
 	return artInstances.at(artifactID.getNum()).get();
 }
 
-const std::vector<ObjectInstanceID> & CMap::getAllTowns()
+const std::vector<ObjectInstanceID> & CMap::getAllTowns() const
 {
 	return towns;
 }
 
-const std::vector<ObjectInstanceID> & CMap::getHeroesOnMap()
+const std::vector<ObjectInstanceID> & CMap::getHeroesOnMap() const
 {
 	return heroesOnMap;
 }
diff --git a/lib/mapping/CMap.h b/lib/mapping/CMap.h
index 44d534c5c..ed7440859 100644
--- a/lib/mapping/CMap.h
+++ b/lib/mapping/CMap.h
@@ -236,10 +236,10 @@ public:
 
 	/// Returns ID's of all heroes that are currently present on map
 	/// Includes all garrisoned and imprisoned heroes
-	const std::vector<ObjectInstanceID> & getHeroesOnMap();
+	const std::vector<ObjectInstanceID> & getHeroesOnMap() const;
 
 	/// Returns ID's of all towns present on map
-	const std::vector<ObjectInstanceID> & getAllTowns();
+	const std::vector<ObjectInstanceID> & getAllTowns() const;
 
 	/// Sets the victory/loss condition objectives ??
 	void checkForObjectives();
diff --git a/server/CGameHandler.cpp b/server/CGameHandler.cpp
index b6b08a5d3..7b4db85ef 100644
--- a/server/CGameHandler.cpp
+++ b/server/CGameHandler.cpp
@@ -438,10 +438,7 @@ void CGameHandler::handleClientDisconnection(std::shared_ptr<CConnection> c)
 	for(auto & playerConnections : connections)
 	{
 		PlayerColor playerId = playerConnections.first;
-		const auto * playerSettings = gameState().getStartInfo()->getPlayersSettings(playerId.getNum());
-		if(!playerSettings)
-			continue;
-		
+
 		auto playerConnection = vstd::find(playerConnections.second, c);
 		if(playerConnection == playerConnections.second.end())
 			continue;
@@ -818,8 +815,8 @@ bool CGameHandler::moveHero(ObjectInstanceID hid, int3 dst, EMovementMode moveme
 
 	const TerrainTile t = *gameInfo().getTile(hmpos);
 	const int3 guardPos = gameState().guardingCreaturePosition(hmpos);
-	CGObjectInstance * objectToVisit = nullptr;
-	CGObjectInstance * guardian = nullptr;
+	const CGObjectInstance * objectToVisit = nullptr;
+	const CGObjectInstance * guardian = nullptr;
 
 	if (!t.visitableObjects.empty())
 		objectToVisit = gameState().getObjInstance(t.visitableObjects.back());
@@ -1003,7 +1000,7 @@ bool CGameHandler::moveHero(ObjectInstanceID hid, int3 dst, EMovementMode moveme
 		// do not visit any other objects, e.g. monoliths to avoid double-teleporting
 		if (objectToVisit)
 		{
-			if (CGTownInstance * town = dynamic_cast<CGTownInstance *>(objectToVisit))
+			if (const CGTownInstance * town = dynamic_cast<const CGTownInstance *>(objectToVisit))
 				objectVisited(town, h);
 		}
 
@@ -2320,7 +2317,7 @@ bool CGameHandler::razeStructure (ObjectInstanceID tid, BuildingID bid)
 
 bool CGameHandler::spellResearch(ObjectInstanceID tid, SpellID spellAtSlot, bool accepted)
 {
-	CGTownInstance *t = gameState().getTown(tid);
+	const CGTownInstance * t = gameState().getTown(tid);
 
 	if(!gameInfo().getSettings().getBoolean(EGameSettings::TOWNS_SPELL_RESEARCH) && complain("Spell research not allowed!"))
 		return false;
@@ -2721,7 +2718,7 @@ bool CGameHandler::bulkMoveArtifacts(const PlayerColor & player, ObjectInstanceI
 	auto & slotsDstSrc = ma.artsPack1;
 
 	// Temporary fitting set for artifacts. Used to select available slots before sending data.
-	CArtifactFittingSet artFittingSet(&gameState(), pdstSet->bearerType());
+	CArtifactFittingSet artFittingSet(&gameInfo(), pdstSet->bearerType());
 
 	auto moveArtifact = [this, &artFittingSet, dstId](const CArtifactInstance * artifact,
 		ArtifactPosition srcSlot, std::vector<MoveArtifactInfo> & slots) -> void
@@ -4288,7 +4285,7 @@ std::shared_ptr<CGObjectInstance> CGameHandler::createNewObject(const int3 & vis
 
 	auto handler = LIBRARY->objtypeh->getHandlerFor(objectID, subID);
 
-	auto o = handler->create(&gameState(), nullptr);
+	auto o = handler->create(&gameInfo(), nullptr);
 	handler->configureObject(o.get(), *randomizer);
 	assert(o->ID == objectID);
 	gameState().getMap().generateUniqueInstanceName(o.get());
@@ -4321,7 +4318,7 @@ void CGameHandler::createWanderingMonster(const int3 & visitablePosition, Creatu
 	cre->gainedArtifact = ArtifactID::NONE;
 	cre->identifier = -1;
 	cre->temppower = static_cast<int64_t>(unitSize) * 1000;
-	cre->addToSlot(SlotID(0), std::make_unique<CStackInstance>(&gameState(), creature, unitSize));
+	cre->addToSlot(SlotID(0), std::make_unique<CStackInstance>(&gameInfo(), creature, unitSize));
 
 	newObject(createdObject, PlayerColor::NEUTRAL);
 }
diff --git a/server/CGameHandler.h b/server/CGameHandler.h
index beb6a33e5..a3fcb78ff 100644
--- a/server/CGameHandler.h
+++ b/server/CGameHandler.h
@@ -11,7 +11,6 @@
 
 #include <vcmi/Environment.h>
 
-#include "../lib/callback/CGameInfoCallback.h"
 #include "../lib/callback/IGameEventCallback.h"
 #include "../lib/LoadProgress.h"
 #include "../lib/ScriptHandler.h"
@@ -29,6 +28,8 @@ class EVictoryLossCheckResult;
 class CRandomGenerator;
 class GameRandomizer;
 
+struct StartInfo;
+struct TerrainTile;
 struct CPackForServer;
 struct NewTurn;
 struct CGarrisonOperationPack;
diff --git a/server/battles/BattleProcessor.cpp b/server/battles/BattleProcessor.cpp
index 7fa59fa85..e0054e925 100644
--- a/server/battles/BattleProcessor.cpp
+++ b/server/battles/BattleProcessor.cpp
@@ -175,7 +175,7 @@ BattleID BattleProcessor::setupBattle(int3 tile, BattleSideArray<const CArmedIns
 
 	//send info about battles
 	BattleStart bs;
-	bs.info = BattleInfo::setupBattle(&gameHandler->gameState(), tile, terrain, battlefieldType, armies, heroes, layout, town);
+	bs.info = BattleInfo::setupBattle(&gameHandler->gameInfo(), tile, terrain, battlefieldType, armies, heroes, layout, town);
 	bs.battleID = gameHandler->gameState().nextBattleID;
 
 	engageIntoBattle(bs.info->getSide(BattleSide::ATTACKER).color);
diff --git a/server/processors/NewTurnProcessor.cpp b/server/processors/NewTurnProcessor.cpp
index c5e022a14..d6383b92b 100644
--- a/server/processors/NewTurnProcessor.cpp
+++ b/server/processors/NewTurnProcessor.cpp
@@ -567,7 +567,7 @@ std::vector<SetMana> NewTurnProcessor::updateHeroesManaPoints()
 
 	for (auto & elem : gameHandler->gameState().players)
 	{
-		for (CGHeroInstance *h : elem.second.getHeroes())
+		for (const CGHeroInstance *h : elem.second.getHeroes())
 		{
 			int32_t newMana = h->getManaNewTurn();
 
@@ -584,7 +584,7 @@ std::vector<SetMovePoints> NewTurnProcessor::updateHeroesMovementPoints()
 
 	for (auto & elem : gameHandler->gameState().players)
 	{
-		for (CGHeroInstance *h : elem.second.getHeroes())
+		for (const CGHeroInstance *h : elem.second.getHeroes())
 		{
 			auto ti = h->getTurnInfo(1);
 			// NOTE: this code executed when bonuses of previous day not yet updated (this happen in NewTurn::applyGs). See issue 2356
diff --git a/server/queries/MapQueries.cpp b/server/queries/MapQueries.cpp
index 56ca4baa3..9db164f82 100644
--- a/server/queries/MapQueries.cpp
+++ b/server/queries/MapQueries.cpp
@@ -13,6 +13,7 @@
 #include "QueriesProcessor.h"
 #include "../CGameHandler.h"
 #include "../TurnTimerHandler.h"
+#include "../../lib/callback/IGameInfoCallback.h"
 #include "../../lib/mapObjects/CGHeroInstance.h"
 #include "../../lib/mapObjects/MiscObjects.h"
 #include "../../lib/networkPacks/PacksForServer.h"