Add custom StaliniumSwordItem with strength buff effect

src/main/java/net/krituximon/stalinium/item/ModItems.java

@@ -22,7 +22,7 @@ public class ModItems {
             () -> new Item(new Item.Properties().jukeboxPlayable(ModSounds.SOVIET_ANTHEM_KEY).stacksTo(1)));
 
     public static final DeferredItem<SwordItem> STALINIUM_SWORD = ITEMS.register("stalinium_sword",
-            () -> new SwordItem(ModTiers.STALINIUM, new Item.Properties()
+            () -> new StaliniumSwordItem(ModTiers.STALINIUM, new Item.Properties()
                     .attributes(SwordItem.createAttributes(ModTiers.STALINIUM, 8, -2.75f))));
 
     public static void register(IEventBus eventBus) {

src/main/java/net/krituximon/stalinium/item/ModTiers.java

@@ -1,11 +1,8 @@
 package net.krituximon.stalinium.item;
 
 import net.minecraft.tags.BlockTags;
-import net.minecraft.tags.TagKey;
 import net.minecraft.world.item.Tier;
-import net.minecraft.world.item.component.Tool;
 import net.minecraft.world.item.crafting.Ingredient;
-import net.minecraft.world.level.block.Block;
 import net.neoforged.neoforge.common.SimpleTier;
 
 public class ModTiers {

src/main/java/net/krituximon/stalinium/item/StaliniumSwordItem.java

@@ -0,0 +1,35 @@
+package net.krituximon.stalinium.item;
+
+import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.effect.MobEffectInstance;
+import net.minecraft.world.effect.MobEffects;
+import net.minecraft.world.entity.LivingEntity;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.item.SwordItem;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.Tier;
+import net.minecraft.world.level.Level;
+
+import java.util.List;
+
+public class StaliniumSwordItem extends SwordItem {
+    public StaliniumSwordItem(Tier tier, Properties props) {
+        super(tier, props);
+    }
+
+    @Override
+    public boolean hurtEnemy(ItemStack stack, LivingEntity target, LivingEntity attacker) {
+        boolean result = super.hurtEnemy(stack, target, attacker);
+        if (!attacker.getCommandSenderWorld().isClientSide) {
+            MobEffectInstance strength = new MobEffectInstance(MobEffects.DAMAGE_BOOST, 100, 0, false, true);
+            attacker.addEffect(strength);
+            Level world = attacker.getCommandSenderWorld();
+            var box = attacker.getBoundingBox().inflate(5.0);
+            List<Player> nearby = world.getEntitiesOfClass(Player.class, box, p -> p instanceof ServerPlayer);
+            for (Player p : nearby) {
+                p.addEffect(strength);
+            }
+        }
+        return result;
+    }
+}