arcane missle initial logic

Items/ArcaneMissle/ArcaneMissle.cs

@@ -0,0 +1,31 @@
+using Terraria;
+using Terraria.GameContent.Creative;
+using Terraria.ModLoader;
+
+namespace YHTMod.Items.ArcaneMissle; 
+
+public class ArcaneMissle : ModItem {
+
+    public override void SetStaticDefaults() {
+        DisplayName.SetDefault("Arcane Missle");
+        Tooltip.SetDefault("Magic damage crits have a chance to shoot a homing arcane missle");
+        CreativeItemSacrificesCatalog.Instance.SacrificeCountNeededByItemId[Type] = 1;
+    }
+
+    public override void SetDefaults() {
+        Item.width = 64;
+        Item.height = 64;
+        Item.accessory = true;
+        Item.damage = 10;
+        Item.DamageType = DamageClass.Magic;
+        Item.noMelee = true;
+        Item.noUseGraphic = true;
+    }
+
+    public override void UpdateAccessory(Player player, bool hideVisual) {
+
+        player.GetModPlayer<YhtPlayer>().arcaneMissle = true;
+        
+        base.UpdateAccessory(player, hideVisual);
+    }
+}

Items/ArcaneMissle/ArcaneMissleBehavior.cs

@@ -0,0 +1,21 @@
+using Terraria;
+using Terraria.ModLoader;
+
+namespace YHTMod.Items.ArcaneMissle; 
+
+public class ArcaneMissleBehavior : GlobalNPC {
+    
+    public override void OnHitByProjectile(NPC npc, Projectile projectile, int damage, float knockback, bool crit) {
+        if (!crit) {
+            base.OnHitByProjectile(npc, projectile, damage, knockback, false);
+            return;
+        }
+        Player player = Main.LocalPlayer;
+        
+        if (player.GetModPlayer<YhtPlayer>().arcaneMissle && projectile.DamageType == DamageClass.Magic) {
+            // player just crit with magic weapon while having arcane missle accessory equipped
+        }
+
+        base.OnHitByProjectile(npc, projectile, damage, knockback, true);
+    }
+}

YhtPlayer.cs

@@ -0,0 +1,15 @@
+using Terraria.ModLoader;
+
+namespace YHTMod; 
+
+public class YhtPlayer : ModPlayer {
+
+    public bool arcaneMissle = false;
+
+    public override void ResetEffects() {
+
+        this.arcaneMissle = false;
+
+        base.ResetEffects();
+    }
+}