diff --git a/forge-game/src/main/java/forge/game/CardTraitBase.java b/forge-game/src/main/java/forge/game/CardTraitBase.java
index 4d84640e782..109d007a1ae 100644
--- a/forge-game/src/main/java/forge/game/CardTraitBase.java
+++ b/forge-game/src/main/java/forge/game/CardTraitBase.java
@@ -36,7 +36,7 @@ import forge.util.ITranslatable;
  * Base class for Triggers,ReplacementEffects and StaticAbilities.
  *
  */
-public abstract class CardTraitBase extends GameObject implements IHasCardView, IHasSVars {
+public abstract class CardTraitBase implements GameObject, IHasCardView, IHasSVars {
 
     /** The host card. */
     protected Card hostCard;
diff --git a/forge-game/src/main/java/forge/game/GameEntity.java b/forge-game/src/main/java/forge/game/GameEntity.java
index 1447b1d78ad..f52612e1e42 100644
--- a/forge-game/src/main/java/forge/game/GameEntity.java
+++ b/forge-game/src/main/java/forge/game/GameEntity.java
@@ -46,7 +46,7 @@ import forge.game.staticability.StaticAbilityCantAttach;
 import forge.game.zone.ZoneType;
 import forge.util.Lang;
 
-public abstract class GameEntity extends GameObject implements IIdentifiable {
+public abstract class GameEntity implements GameObject, IIdentifiable {
     protected int id;
     private String name = "";
     protected CardCollection attachedCards = new CardCollection();
diff --git a/forge-game/src/main/java/forge/game/GameObject.java b/forge-game/src/main/java/forge/game/GameObject.java
index bf5141cd913..976bbc6b736 100644
--- a/forge-game/src/main/java/forge/game/GameObject.java
+++ b/forge-game/src/main/java/forge/game/GameObject.java
@@ -4,9 +4,9 @@ import forge.game.card.Card;
 import forge.game.player.Player;
 import forge.game.spellability.SpellAbility;
 
-public abstract class GameObject {
+public interface GameObject {
 
-    public boolean canBeTargetedBy(final SpellAbility sa) {
+    public default boolean canBeTargetedBy(final SpellAbility sa) {
         return false;
     }
     
@@ -22,7 +22,7 @@ public abstract class GameObject {
      * @param spellAbility
      * @return true, if is valid
      */
-    public boolean isValid(final String[] restrictions, final Player sourceController, final Card source, CardTraitBase spellAbility) {
+    public default boolean isValid(final String[] restrictions, final Player sourceController, final Card source, CardTraitBase spellAbility) {
         for (final String restriction : restrictions) {
             if (this.isValid(restriction, sourceController, source, spellAbility)) {
                 return true;
@@ -43,7 +43,7 @@ public abstract class GameObject {
      * @param spellAbility
      * @return true, if is valid
      */
-    public boolean isValid(final String restriction, final Player sourceController, final Card source, CardTraitBase spellAbility) {
+    public default boolean isValid(final String restriction, final Player sourceController, final Card source, CardTraitBase spellAbility) {
         return false;
     }
 
@@ -59,7 +59,7 @@ public abstract class GameObject {
      * @param spellAbility
      * @return true, if successful
      */
-    public boolean hasProperty(final String property, final Player sourceController, final Card source, CardTraitBase spellAbility) {
+    public default boolean hasProperty(final String property, final Player sourceController, final Card source, CardTraitBase spellAbility) {
         return false;
     }
 }
\ No newline at end of file
diff --git a/forge-game/src/main/java/forge/game/card/CardState.java b/forge-game/src/main/java/forge/game/card/CardState.java
index 289520ecf28..0ddad73e783 100644
--- a/forge-game/src/main/java/forge/game/card/CardState.java
+++ b/forge-game/src/main/java/forge/game/card/CardState.java
@@ -56,7 +56,7 @@ import java.util.Set;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
-public class CardState extends GameObject implements IHasSVars, ITranslatable {
+public class CardState implements GameObject, IHasSVars, ITranslatable {
     private String name = "";
     private CardType type = new CardType(false);
     private ManaCost manaCost = ManaCost.NO_COST;