diff --git a/Source/missiles.cpp b/Source/missiles.cpp
index 4e0e090bc3db..bbf6fe076093 100644
--- a/Source/missiles.cpp
+++ b/Source/missiles.cpp
@@ -239,7 +239,7 @@ bool MonsterMHit(const Player &player, int monsterId, int mindam, int maxdam, in
 	if (t == MissileID::BoneSpirit) {
 		dam = monster.hitPoints / 3 >> 6;
 	} else {
-		dam = mindam + GenerateRnd(maxdam - mindam + 1);
+		dam = RandomIntBetween(mindam, maxdam);
 	}
 
 	if (missileData.isArrow() && damageType == DamageType::Physical) {
@@ -3304,7 +3304,7 @@ void ProcessLightningControl(Missile &missile)
 		dam = (GenerateRnd(2) + GenerateRnd(Players[missile._misource].getCharacterLevel()) + 2) << 6;
 	} else {
 		auto &monster = Monsters[missile._misource];
-		dam = 2 * (monster.minDamage + GenerateRnd(monster.maxDamage - monster.minDamage + 1));
+		dam = 2 * RandomIntBetween(monster.minDamage, monster.maxDamage);
 	}
 
 	SpawnLightning(missile, dam);
diff --git a/Source/monster.cpp b/Source/monster.cpp
index db36cae3100f..5979e4f5f01a 100644
--- a/Source/monster.cpp
+++ b/Source/monster.cpp
@@ -149,7 +149,7 @@ void InitMonster(Monster &monster, Direction rd, size_t typeIndex, Point positio
 	monster.animInfo.tickCounterOfCurrentFrame = GenerateRnd(monster.animInfo.ticksPerFrame - 1);
 	monster.animInfo.currentFrame = GenerateRnd(monster.animInfo.numberOfFrames - 1);
 
-	int maxhp = monster.data().hitPointsMinimum + GenerateRnd(monster.data().hitPointsMaximum - monster.data().hitPointsMinimum + 1);
+	int maxhp = RandomIntBetween(monster.data().hitPointsMinimum, monster.data().hitPointsMaximum);
 	if (monster.type().type == MT_DIABLO && !gbIsHellfire) {
 		maxhp /= 2;
 	}
@@ -1086,7 +1086,7 @@ void MonsterAttackMonster(Monster &attacker, Monster &target, int hper, int mind
 	if (hit >= hper)
 		return;
 
-	int dam = (mind + GenerateRnd(maxd - mind + 1)) << 6;
+	int dam = RandomIntBetween(mind, maxd) << 6;
 	ApplyMonsterDamage(DamageType::Physical, target, dam);
 
 	if (attacker.isPlayerMinion()) {
@@ -1191,7 +1191,8 @@ void MonsterAttackPlayer(Monster &monster, Player &player, int hit, int minDam,
 			}
 		}
 	}
-	int dam = (minDam << 6) + GenerateRnd(((maxDam - minDam) << 6) + 1);
+	// New method fixes a bug which caused the maximum possible damage value to be 63/64ths too low.
+	int dam = RandomIntBetween(minDam, maxDam) << 6;
 	dam = std::max(dam + (player._pIGetHit << 6), 64);
 	if (&player == MyPlayer) {
 		if (player.wReflections > 0) {
@@ -2650,7 +2651,7 @@ void CounselorAi(Monster &monster)
 		if (distanceToEnemy >= 2) {
 			if (v < 5 * (monster.intelligence + 10) && LineClearMissile(monster.position.tile, monster.enemyPosition)) {
 				constexpr MissileID MissileTypes[4] = { MissileID::Firebolt, MissileID::ChargedBolt, MissileID::LightningControl, MissileID::Fireball };
-				StartRangedAttack(monster, MissileTypes[monster.intelligence], monster.minDamage + GenerateRnd(monster.maxDamage - monster.minDamage + 1));
+				StartRangedAttack(monster, MissileTypes[monster.intelligence], RandomIntBetween(monster.minDamage, monster.maxDamage));
 			} else if (GenerateRnd(100) < 30) {
 				monster.goal = MonsterGoal::Move;
 				monster.goalVar1 = 0;
diff --git a/Source/player.cpp b/Source/player.cpp
index 66261e5861b3..c524369fd6dc 100644
--- a/Source/player.cpp
+++ b/Source/player.cpp
@@ -600,12 +600,12 @@ bool PlrHitMonst(Player &player, Monster &monster, bool adjacentDamage = false)
 	}
 
 	if (gbIsHellfire && HasAllOf(player._pIFlags, ItemSpecialEffect::FireDamage | ItemSpecialEffect::LightningDamage)) {
-		int midam = player._pIFMinDam + GenerateRnd(player._pIFMaxDam - player._pIFMinDam);
+		int midam = RandomIntBetween(player._pIFMinDam, player._pIFMaxDam);
 		AddMissile(player.position.tile, player.position.temp, player._pdir, MissileID::SpectralArrow, TARGET_MONSTERS, player, midam, 0);
 	}
 	int mind = player._pIMinDam;
 	int maxd = player._pIMaxDam;
-	int dam = GenerateRnd(maxd - mind + 1) + mind;
+	int dam = RandomIntBetween(mind, maxd);
 	dam += dam * player._pIBonusDam / 100;
 	dam += player._pIBonusDamMod;
 	int dam2 = dam << 6;
@@ -773,7 +773,7 @@ bool PlrHitPlr(Player &attacker, Player &target)
 
 	int mind = attacker._pIMinDam;
 	int maxd = attacker._pIMaxDam;
-	int dam = GenerateRnd(maxd - mind + 1) + mind;
+	int dam = RandomIntBetween(mind, maxd);
 	dam += (dam * attacker._pIBonusDam) / 100;
 	dam += attacker._pIBonusDamMod + attacker._pDamageMod;
 
@@ -920,7 +920,7 @@ bool DoRangeAttack(Player &player)
 			mistype = MissileID::LightningArrow;
 		}
 		if (HasAllOf(player._pIFlags, ItemSpecialEffect::FireArrows | ItemSpecialEffect::LightningArrows)) {
-			dmg = player._pIFMinDam + GenerateRnd(player._pIFMaxDam - player._pIFMinDam);
+			dmg = RandomIntBetween(player._pIFMinDam, player._pIFMaxDam);
 			mistype = MissileID::SpectralArrow;
 		}