diff --git a/Mage.Client/src/main/java/mage/client/util/audio/MusicPlayer.java b/Mage.Client/src/main/java/mage/client/util/audio/MusicPlayer.java
index cd1613bbcaf..83b73777dc6 100644
--- a/Mage.Client/src/main/java/mage/client/util/audio/MusicPlayer.java
+++ b/Mage.Client/src/main/java/mage/client/util/audio/MusicPlayer.java
@@ -7,6 +7,7 @@ import java.util.concurrent.TimeUnit;
 import javax.sound.sampled.*;
 import mage.client.constants.Constants;
 import mage.client.dialog.PreferencesDialog;
+import mage.util.RandomUtil;
 import org.apache.log4j.Logger;
 
 /**
@@ -127,7 +128,7 @@ public class MusicPlayer {
             } catch (Exception e) {
             }
             while (!stopped) {
-                int it = (int) Math.abs(Math.random() * (filelist.getItemCount()));
+                int it = (int) Math.abs(RandomUtil.nextDouble() * (filelist.getItemCount()));
                 File file = new File(filepath + filelist.getItem(it));
                 load(file);
                 Thread PlayThread = new Thread(new PlayThread());
diff --git a/Mage.Client/src/main/java/org/mage/plugins/theme/ThemePluginImpl.java b/Mage.Client/src/main/java/org/mage/plugins/theme/ThemePluginImpl.java
index 7d12660d5a9..9869605f649 100644
--- a/Mage.Client/src/main/java/org/mage/plugins/theme/ThemePluginImpl.java
+++ b/Mage.Client/src/main/java/org/mage/plugins/theme/ThemePluginImpl.java
@@ -11,6 +11,7 @@ import mage.client.dialog.PreferencesDialog;
 import mage.components.ImagePanel;
 import mage.components.ImagePanelStyle;
 import mage.interfaces.plugin.ThemePlugin;
+import mage.util.RandomUtil;
 import net.xeoh.plugins.base.annotations.PluginImplementation;
 import net.xeoh.plugins.base.annotations.events.PluginLoaded;
 import net.xeoh.plugins.base.annotations.meta.Author;
@@ -111,7 +112,7 @@ public class ThemePluginImpl implements ThemePlugin {
     private BufferedImage loadbuffer_random() throws IOException {
         BufferedImage res;
         if (loadimages()) {
-            int it = (int) Math.abs(Math.random() * (flist.getItemCount()));
+            int it = (int) Math.abs(RandomUtil.nextDouble() * (flist.getItemCount()));
             String filename = BackgroundDir + flist.getItem(it);
             res = ImageIO.read(new File(filename));
             return res;
diff --git a/Mage.Server.Plugins/Mage.Player.AIMCTS/src/mage/player/ai/MCTSNode.java b/Mage.Server.Plugins/Mage.Player.AIMCTS/src/mage/player/ai/MCTSNode.java
index 463a6cce7c9..11e5c83e8ee 100644
--- a/Mage.Server.Plugins/Mage.Player.AIMCTS/src/mage/player/ai/MCTSNode.java
+++ b/Mage.Server.Plugins/Mage.Player.AIMCTS/src/mage/player/ai/MCTSNode.java
@@ -17,9 +17,9 @@ import mage.abilities.common.PassAbility;
 import mage.cards.Card;
 import mage.game.Game;
 import mage.game.combat.Combat;
-import mage.game.combat.CombatGroup;
 import mage.game.turn.Step.StepPart;
 import mage.players.Player;
+import mage.util.RandomUtil;
 import org.apache.log4j.Logger;
 
 /**
@@ -113,7 +113,7 @@ public class MCTSNode {
                     uct = ((node.visits - node.wins) / (node.visits)) + (selectionCoefficient * Math.sqrt(Math.log(visits) / (node.visits)));
             else
                 // ensure that a random unvisited node is played first
-                uct = 10000 + 1000 * Math.random();
+                uct = 10000 + 1000 * RandomUtil.nextDouble();
             if (uct > bestValue) {
                 bestChild = node;
                 bestValue = uct;
diff --git a/Mage.Sets/src/mage/cards/t/TyrantOfDiscord.java b/Mage.Sets/src/mage/cards/t/TyrantOfDiscord.java
index 13a8ae74750..61b836d2f1a 100644
--- a/Mage.Sets/src/mage/cards/t/TyrantOfDiscord.java
+++ b/Mage.Sets/src/mage/cards/t/TyrantOfDiscord.java
@@ -16,6 +16,7 @@ import mage.game.Game;
 import mage.game.permanent.Permanent;
 import mage.players.Player;
 import mage.target.common.TargetOpponent;
+import mage.util.RandomUtil;
 
 /**
  * @author noxx
@@ -70,7 +71,7 @@ class TyrantOfDiscordEffect extends OneShotEffect {
             while (!stop) {
                 int count = game.getBattlefield().countAll(new FilterPermanent(), opponent.getId(), game);
                 if (count > 0) {
-                    int random = (int)(Math.random()*count);
+                    int random = (int)(RandomUtil.nextDouble() * count);
                     int index = 0;
                     for (Permanent permanent : game.getBattlefield().getAllActivePermanents(opponent.getId())) {
                         if (index == random) {