diff --git a/src/main/java/net/theevilreaper/xerus/api/ItemShiftOption.java b/src/main/java/net/theevilreaper/xerus/api/ItemShiftOption.java
index a61f6d0..78e766e 100644
--- a/src/main/java/net/theevilreaper/xerus/api/ItemShiftOption.java
+++ b/src/main/java/net/theevilreaper/xerus/api/ItemShiftOption.java
@@ -2,15 +2,16 @@
 
 import net.minestom.server.entity.Player;
 import net.minestom.server.utils.validate.Check;
+import org.jetbrains.annotations.Nullable;
 
-import java.util.List;
+import java.util.Collection;
 import java.util.Locale;
 
 /**
  * Contains some methods that help to set the player items.
  *
  * @author theEvilReaper
- * @version 1.1.0
+ * @version 1.3.0
  * @since 1.2.0
  **/
 @FunctionalInterface
@@ -23,10 +24,10 @@ public interface ItemShiftOption {
      * @param locale       the locale to determine the right items
      * @param shiftedSlots specifies whether the items should be added in a different order
      */
-    void setEquipment(Player player, Locale locale, int... shiftedSlots);
+    void setEquipment(Player player, @Nullable Locale locale, int @Nullable ... shiftedSlots);
 
     /**
-     * Sets an equipment to an specific player.
+     * Sets equipment to a specific player.
      *
      * @param player       the player who receives the equipment
      * @param shiftedSlots array containing shifted slots for the items
@@ -42,11 +43,9 @@ default void setEquipment(Player player, int... shiftedSlots) {
      * @param players      the players who receive the equipment
      * @param shiftedSlots array containing shifted slots for the items
      */
-    default void setEquipment(List<Player> players, int... shiftedSlots) {
+    default void setEquipment(Collection<Player> players, int... shiftedSlots) {
         if (players.isEmpty()) return;
 
-        for (int i = 0; i < players.size(); i++) {
-            this.setEquipment(players.get(i), shiftedSlots);
-        }
+        players.forEach(player -> setEquipment(player, shiftedSlots));
     }
 }
diff --git a/src/main/java/net/theevilreaper/xerus/api/Joinable.java b/src/main/java/net/theevilreaper/xerus/api/Joinable.java
index cbbafa5..c6e2e37 100644
--- a/src/main/java/net/theevilreaper/xerus/api/Joinable.java
+++ b/src/main/java/net/theevilreaper/xerus/api/Joinable.java
@@ -3,76 +3,76 @@
 import net.minestom.server.entity.Player;
 import org.jetbrains.annotations.Nullable;
 
-import java.util.Set;
+import java.util.Collection;
 import java.util.function.Consumer;
 
 /**
- * The interface provides some method to add a single player object or a set off players.
+ * The interface provides some method to add a single player object or a collection of players.
  * Each developer can implement the interface into his class but must write his own logic for the methods.
  *
  * @author theEvilReaper
- * @version 1.1.0
+ * @version 1.2.0
  * @since 1.0.0
  */
 public interface Joinable {
 
     /**
      * Add a single player
-     * @param paramPlayer The player to add
+     * @param player The player to add
      */
-    default void addPlayer(Player paramPlayer) {
-        this.addPlayer(paramPlayer, null);
+    default void addPlayer(Player player) {
+        this.addPlayer(player, null);
     }
 
     /**
      * Add a single {@link Player} entry to a structure.
-     * @param paramPlayer the player to add
+     * @param player the player to add
      * @param consumer a consumer which is called to execute some logic
      */
-    void addPlayer(Player paramPlayer, @Nullable Consumer<Player> consumer);
+    void addPlayer(Player player, @Nullable Consumer<Player> consumer);
 
     /**
-     * Add a set off players
-     * @param players The set which contains the players to add
+     * Add a collection of players
+     * @param players The collection which contains the players to add
      */
-    default void addPlayers(Set<Player> players) {
+    default void addPlayers(Collection<Player> players) {
         this.addPlayers(players, null);
     }
 
     /**
-     * Add a set off players
-     * @param players The set which contains the players to add
+     * Add a collection of players
+     * @param players The collection which contains the players to add
      * @param consumer a consumer which is called to execute some logic
      */
-    void addPlayers(Set<Player> players, @Nullable Consumer<Player> consumer);
+    void addPlayers(Collection<Player> players, @Nullable Consumer<Player> consumer);
 
     /**
      * Remove a single player
-     * @param paramPlayer The player to remove
+     * @param player The player to remove
      */
-    default void removePlayer(Player paramPlayer) {
-        this.removePlayer(paramPlayer, null);
+    default void removePlayer(Player player) {
+        this.removePlayer(player, null);
     }
 
     /**
      * Remove a single {@link Player} entry from a structure.
-     * @param paramPlayer the player to remove
+     * @param player the player to remove
      * @param consumer a consumer which is called to execute some logic
      */
-    void removePlayer(Player paramPlayer, @Nullable Consumer<Player> consumer);
+    void removePlayer(Player player, @Nullable Consumer<Player> consumer);
 
     /**
-     * Remove a set off players
-     * @param players The set which contains the players to remove
+     * Remove a collection of players
+     * @param players The collection which contains the players to remove
      */
-    default void removePlayers(Set<Player> players) {
+    default void removePlayers(Collection<Player> players) {
         this.removePlayers(players, null);
     }
 
     /**
-     * Remove a set off players
-     * @param players The set which contains the players to remove
+     * Remove a collection of players
+     * @param players The collection which contains the players to remove
      * @param consumer a consumer which is called to execute some logic
      */
-    void removePlayers(Set<Player> players, @Nullable Consumer<Player> consumer);
+    void removePlayers(Collection<Player> players, @Nullable Consumer<Player> consumer);
 }
\ No newline at end of file
diff --git a/src/main/java/net/theevilreaper/xerus/api/team/Team.java b/src/main/java/net/theevilreaper/xerus/api/team/Team.java
index a11aece..b687cc1 100644
--- a/src/main/java/net/theevilreaper/xerus/api/team/Team.java
+++ b/src/main/java/net/theevilreaper/xerus/api/team/Team.java
@@ -11,6 +11,7 @@
 import net.theevilreaper.xerus.api.team.event.TeamAction;
 import org.jetbrains.annotations.*;
 
+import java.util.Collection;
 import java.util.Comparator;
 import java.util.Set;
 import java.util.function.Consumer;
@@ -75,7 +76,7 @@ default void addPlayer(@NotNull Player player, @Nullable Consumer<Player> consum
      * @param consumer a consumer which is called to execute some logic
      */
     @Override
-    default void addPlayers(@NotNull Set<Player> players, @Nullable Consumer<Player> consumer) {
+    default void addPlayers(@NotNull Collection<Player> players, @Nullable Consumer<Player> consumer) {
         if (players.isEmpty()) return;
         players.removeIf(player -> !getPlayers().add(player));
         Runnable successCallback = consumer == null ? EMPTY : () -> getPlayers().forEach(consumer);
@@ -103,7 +104,7 @@ default void removePlayer(@NotNull Player paramPlayer, @Nullable Consumer<Player
      * @param consumer a consumer which is called to execute some logic
      */
     @Override
-    default void removePlayers(@NotNull Set<Player> players, @Nullable Consumer<Player> consumer) {
+    default void removePlayers(@NotNull Collection<Player> players, @Nullable Consumer<Player> consumer) {
         if (players.isEmpty()) return;
         players.removeIf(player -> getPlayers().contains(player));
         Runnable successCallback = consumer == null ? EMPTY : () -> getPlayers().forEach(consumer);
diff --git a/src/main/java/net/theevilreaper/xerus/api/team/event/MultiPlayerTeamEvent.java b/src/main/java/net/theevilreaper/xerus/api/team/event/MultiPlayerTeamEvent.java
index 1f3fab6..0bf9e4f 100644
--- a/src/main/java/net/theevilreaper/xerus/api/team/event/MultiPlayerTeamEvent.java
+++ b/src/main/java/net/theevilreaper/xerus/api/team/event/MultiPlayerTeamEvent.java
@@ -6,20 +6,20 @@
 import net.minestom.server.event.trait.CancellableEvent;
 import org.jetbrains.annotations.NotNull;
 
-import java.util.Set;
+import java.util.Collection;
 
 /**
  * The event will be fired if an action is applied to a team where more than one player is involved.
  * There is a separate event for it, so that the event is called with only one player less
  *
  * @author theEvilReaper
- * @version 1.1.0
+ * @version 1.2.0
  * @since 1.0.11
  **/
 public class MultiPlayerTeamEvent implements Event, CancellableEvent {
 
     private final Team team;
-    private final Set<Player> players;
+    private final Collection<Player> players;
     private final TeamAction action;
     private boolean cancelled;
 
@@ -27,10 +27,10 @@ public class MultiPlayerTeamEvent implements Event, CancellableEvent {
      * Event is called when multiple players interact with a team.
      *
      * @param team       the team which is involved in the event
-     * @param players    the set with the players who are involved in the event
+     * @param players    the collection with the players who are involved in the event
      * @param teamAction the action for the event
      */
-    public MultiPlayerTeamEvent(@NotNull Team team, @NotNull Set<Player> players, @NotNull TeamAction teamAction) {
+    public MultiPlayerTeamEvent(@NotNull Team team, @NotNull Collection<Player> players, @NotNull TeamAction teamAction) {
         this.team = team;
         this.players = players;
         this.action = teamAction;
@@ -59,10 +59,10 @@ public boolean isCancelled() {
     /**
      * Returns the players who are involved in this event.
      *
-     * @return the set with the involved players
+     * @return the collection with the involved players
      */
     @NotNull
-    public Set<Player> getPlayers() {
+    public Collection<Player> getPlayers() {
         return players;
     }
 
diff --git a/src/test/java/net/theevilreaper/xerus/api/JoinableTest.java b/src/test/java/net/theevilreaper/xerus/api/JoinableTest.java
index 1374340..b671fee 100644
--- a/src/test/java/net/theevilreaper/xerus/api/JoinableTest.java
+++ b/src/test/java/net/theevilreaper/xerus/api/JoinableTest.java
@@ -50,4 +50,20 @@ void testMultipleOperation(Env env) {
         this.joinable.removePlayers(players);
         assertTrue(this.joinable.getPlayers().isEmpty());
     }
+
+    @Test
+    void testMultipleOperationWithList(Env env) {
+        final Instance instance = env.createFlatInstance();
+        final var playersList = java.util.List.of(
+                env.createPlayer(instance, Pos.ZERO),
+                env.createPlayer(instance, Pos.ZERO)
+        );
+
+        assertTrue(this.joinable.getPlayers().isEmpty());
+        this.joinable.addPlayers(playersList);
+        assertEquals(2, this.joinable.getPlayers().size());
+
+        this.joinable.removePlayers(playersList);
+        assertTrue(this.joinable.getPlayers().isEmpty());
+    }
 }
diff --git a/src/test/java/net/theevilreaper/xerus/api/mocks/TestJoinableImpl.java b/src/test/java/net/theevilreaper/xerus/api/mocks/TestJoinableImpl.java
index dd85765..6c9f56d 100644
--- a/src/test/java/net/theevilreaper/xerus/api/mocks/TestJoinableImpl.java
+++ b/src/test/java/net/theevilreaper/xerus/api/mocks/TestJoinableImpl.java
@@ -5,6 +5,7 @@
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.Collection;
 import java.util.HashSet;
 import java.util.Set;
 import java.util.function.Consumer;
@@ -18,47 +19,55 @@ public TestJoinableImpl() {
     }
 
     @Override
-    public void addPlayer(@NotNull Player paramPlayer) {
-        this.players.add(paramPlayer);
+    public void addPlayer(@NotNull Player player) {
+        this.players.add(player);
     }
 
     @Override
-    public void addPlayer(@NotNull Player paramPlayer, @Nullable Consumer<Player> consumer) {
-        this.players.add(paramPlayer);
+    public void addPlayer(@NotNull Player player, @Nullable Consumer<Player> consumer) {
+        this.players.add(player);
 
         if (consumer != null) {
-            consumer.accept(paramPlayer);
+            consumer.accept(player);
         }
     }
 
     @Override
-    public void addPlayers(@NotNull Set<Player> players) {
+    public void addPlayers(@NotNull Collection<Player> players) {
         this.players.addAll(players);
     }
 
     @Override
-    public void addPlayers(@NotNull Set<Player> players, @Nullable Consumer<Player> consumer) {
-
+    public void addPlayers(@NotNull Collection<Player> players, @Nullable Consumer<Player> consumer) {
+        this.players.addAll(players);
+        if (consumer != null) {
+            players.forEach(consumer);
+        }
     }
 
     @Override
-    public void removePlayer(@NotNull Player paramPlayer) {
-        this.players.remove(paramPlayer);
+    public void removePlayer(@NotNull Player player) {
+        this.players.remove(player);
     }
 
     @Override
-    public void removePlayer(@NotNull Player paramPlayer, @Nullable Consumer<Player> consumer) {
-
+    public void removePlayer(@NotNull Player player, @Nullable Consumer<Player> consumer) {
+        if (this.players.remove(player) && consumer != null) {
+            consumer.accept(player);
+        }
     }
 
     @Override
-    public void removePlayers(@NotNull Set<Player> players) {
+    public void removePlayers(@NotNull Collection<Player> players) {
         this.players.removeAll(players);
     }
 
     @Override
-    public void removePlayers(@NotNull Set<Player> players, @Nullable Consumer<Player> consumer) {
-
+    public void removePlayers(@NotNull Collection<Player> players, @Nullable Consumer<Player> consumer) {
+        this.players.removeAll(players);
+        if (consumer != null) {
+            players.forEach(consumer);
+        }
     }
 
     public Set<Player> getPlayers() {