diff --git a/hwe/func.php b/hwe/func.php
index 8680cf94..b697723e 100644
--- a/hwe/func.php
+++ b/hwe/func.php
@@ -2085,13 +2085,31 @@ function nextRuler(General $general)
 
     //npc or npc유저인 경우 후계 찾기
     if (!$fiction && $general->getNPCType() > 0) {
-        $candidate = $db->queryFirstRow(
-            'SELECT no,name,officer_level,IF(ABS(affinity-%i)>75,150-ABS(affinity-%i),ABS(affinity-%i)) as npcmatch2 from general where nation=%i and officer_level!=12 and 1 <= npc and npc<=3 order by npcmatch2,rand() LIMIT 1',
+        $rng = new RandUtil(new LiteHashDRBG(Util::simpleSerialize(
+            UniqueConst::$hiddenSeed,
+            'NextNPCRuler',
+            $year,
+            $month,
+            $general->getID(),
+        )));
+        $rawCandidates = $db->query(
+            'SELECT no,name,officer_level,IF(ABS(affinity-%i)>75,150-ABS(affinity-%i),ABS(affinity-%i)) as npcmatch2 from general where nation=%i and officer_level!=12 and 1 <= npc and npc<=3 order by npcmatch2 asc',
             $general->getVar('affinity'),
             $general->getVar('affinity'),
             $general->getVar('affinity'),
             $nationID
         );
+        if ($rawCandidates) {
+            $candidates = [];
+            $minNPCMatch = $rawCandidates[0]['npcmatch2'];
+            foreach ($rawCandidates as $candidate) {
+                if (!$candidate['npcmatch2'] == $minNPCMatch) {
+                    break;
+                }
+                $candidates[] = $candidate;
+            }
+            $candidate = $rng->choice($candidates);
+        }
     }
     if (!$candidate) {
         $candidate = $db->queryFirstRow(
diff --git a/hwe/func_gamerule.php b/hwe/func_gamerule.php
index da488e7c..0c7cc630 100644
--- a/hwe/func_gamerule.php
+++ b/hwe/func_gamerule.php
@@ -396,7 +396,7 @@ function postUpdateMonthly(RandUtil $rng)
 
         //약간의 랜덤치 부여 (95% ~ 105%)
 
-        $nation['power'] = Util::round($nation['power'] * (rand() % 101 + 950) / 1000);
+        $nation['power'] = Util::round($nation['power'] * $rng->nextRange(0.95, 1.05));
         $powerValues['maxPower'] = max($powerValues['maxPower'] ?? 0, $nation['power']);
         $powerValues['maxCrew'] = max($powerValues['maxCrew'] ?? 0, Util::toInt($nation['totalCrew']));
 
diff --git a/hwe/j_get_select_npc_token.php b/hwe/j_get_select_npc_token.php
index ec6d0344..0227114d 100644
--- a/hwe/j_get_select_npc_token.php
+++ b/hwe/j_get_select_npc_token.php
@@ -126,7 +126,7 @@ while(count($pickResult) < $pickLimit){
     }
 }
 
-$newNonce = mt_rand(0, 0xfffffff);
+$newNonce = random_int(0, 0xfffffff);
 
 $validSecond = max(VALID_SECOND, $turnterm*40);
 $pickMoreSecond = max(PICK_MORE_SECOND, Util::round(pow($turnterm, 0.672)*8));
diff --git a/hwe/j_myBossInfo.php b/hwe/j_myBossInfo.php
index 0e74958e..0ee36a0c 100644
--- a/hwe/j_myBossInfo.php
+++ b/hwe/j_myBossInfo.php
@@ -241,34 +241,43 @@ function do추방(General $general, int $myOfficerLevel):?string{
     }
     $general->setVar('troop', 0);
 
-    if($general->getNPCType() >= 2 && Util::randBool(GameConst::$npcBanMessageProb)) {
+    if($general->getNPCType() >= 2){
+        $rng = new RandUtil(new LiteHashDRBG(Util::simpleSerialize(
+            UniqueConst::$hiddenSeed,
+            'BanNPC',
+            $env['year'],
+            $env['month'],
+            $general->getID(),
+        )));
+        if ($rng->nextBool(GameConst::$npcBanMessageProb)) {
 
-        $str = Util::choiceRandom([
-            '날 버리다니... 곧 전장에서 복수해주겠다...',
-            '추방이라... 내가 무얼 잘못했단 말인가...',
-            '어디 추방해가면서 잘되나 보자... 꼭 복수하겠다...',
-            '인덕이 제일이거늘... 추방이 웬말인가... 저주한다!',
-            '날 추방했으니 그 복수로 적국에 정보를 팔아 넘겨야겠군요. 그럼 이만.'
-        ]);
+            $str = $rng->choice([
+                '날 버리다니... 곧 전장에서 복수해주겠다...',
+                '추방이라... 내가 무얼 잘못했단 말인가...',
+                '어디 추방해가면서 잘되나 보자... 꼭 복수하겠다...',
+                '인덕이 제일이거늘... 추방이 웬말인가... 저주한다!',
+                '날 추방했으니 그 복수로 적국에 정보를 팔아 넘겨야겠군요. 그럼 이만.'
+            ]);
 
-        $src = new MessageTarget(
-            $generalID,
-            $generalName,
-            $nationID,
-            $nation['name'],
-            $nation['color'],
-            GetImageURL($general->getVar('imgsvr'), $general->getVar('picture'))
-        );
-        $msg = new Message(
-            Message::MSGTYPE_PUBLIC,
-            $src,
-            $src,
-            $str,
-            new \DateTime(),
-            new \DateTime('9999-12-31'),
-            []
-        );
-        $msg->send();
+            $src = new MessageTarget(
+                $generalID,
+                $generalName,
+                $nationID,
+                $nation['name'],
+                $nation['color'],
+                GetImageURL($general->getVar('imgsvr'), $general->getVar('picture'))
+            );
+            $msg = new Message(
+                Message::MSGTYPE_PUBLIC,
+                $src,
+                $src,
+                $str,
+                new \DateTime(),
+                new \DateTime('9999-12-31'),
+                []
+            );
+            $msg->send();
+        }
     }
 
     if($env['year'] < $env['startyear']+3) {
diff --git a/hwe/process_war.php b/hwe/process_war.php
index d910ade6..03058321 100644
--- a/hwe/process_war.php
+++ b/hwe/process_war.php
@@ -590,8 +590,8 @@ function ConquerCity(array $admin, General $general, array $city)
         $loseGeneralGold = 0;
         $loseGeneralRice = 0;
         foreach ($oldNationGenerals as $oldGeneral) {
-            $loseGold = intdiv($oldGeneral->getVar('gold') * (rand() % 30 + 20), 100);
-            $loseRice = intdiv($oldGeneral->getVar('rice') * (rand() % 30 + 20), 100);
+            $loseGold = Util::toInt($oldGeneral->getVar('gold') * $rng->nextRange(0.2, 0.5));
+            $loseRice = Util::toInt($oldGeneral->getVar('rice') * $rng->nextRange(0.2, 0.5));
             $oldGeneral->getLogger()->pushGeneralActionLog(
                 "도주하며 금<C>$loseGold</> 쌀<C>$loseRice</>을 분실했습니다.",
                 ActionLogger::PLAIN
diff --git a/hwe/sammo/API/General/Join.php b/hwe/sammo/API/General/Join.php
index b54cafab..ea57433a 100644
--- a/hwe/sammo/API/General/Join.php
+++ b/hwe/sammo/API/General/Join.php
@@ -331,7 +331,7 @@ class Join extends \sammo\BaseAPI
             $character = $rng->choice(GameConst::$availablePersonality);
         }
         //상성 랜덤
-        $affinity = rand() % 150 + 1;
+        $affinity = $rng->nextRangeInt(1, 150);
 
         ########## 회원정보 테이블에 입력값을 등록한다. ##########
         $db->insert('general', [
diff --git a/hwe/sammo/Scenario/GeneralBuilder.php b/hwe/sammo/Scenario/GeneralBuilder.php
index 190bc666..ea375958 100644
--- a/hwe/sammo/Scenario/GeneralBuilder.php
+++ b/hwe/sammo/Scenario/GeneralBuilder.php
@@ -652,7 +652,7 @@ class GeneralBuilder{
             $killturn = $this->killturn;
         }
         else if($this->birth !== null){
-            $killturn = ($this->death - $year) * 12 + mt_rand(0, 11) + $month - 1;
+            $killturn = ($this->death - $year) * 12 + $this->rng->nextRangeInt(0, 11) + $month - 1;
         }
         else{
             throw new \InvalidArgumentException();
diff --git a/hwe/sammo/WarUnit.php b/hwe/sammo/WarUnit.php
index 7ad3c665..785329a0 100644
--- a/hwe/sammo/WarUnit.php
+++ b/hwe/sammo/WarUnit.php
@@ -286,7 +286,7 @@ class WarUnit
             //최소 전투력 50 보장
             $warPower = max(0, $warPower);
             $warPower = ($warPower + 100) / 2;
-            $warPower = rand($warPower, 100);
+            $warPower = $this->rng->nextRangeInt($warPower, 100);
         }
 
         $warPower *= $this->getComputedAtmos();
diff --git a/i_entrance/j_icon_change.php b/i_entrance/j_icon_change.php
index 99371dfc..98cabcd8 100644
--- a/i_entrance/j_icon_change.php
+++ b/i_entrance/j_icon_change.php
@@ -70,7 +70,7 @@ if(!is_uploaded_file($image['tmp_name'])) {
     //이미지 저장
 
     while(true){
-        $newPicName = dechex(rand(0x000000f,0xfffffff)).$newExt;
+        $newPicName = bin2hex(random_bytes(4)).$newExt;
         $dest = AppConf::getUserIconPathFS().'/'.$newPicName;
         if(file_exists($dest)){
             continue;