Terraria Mod Sword

DrewSword.cs

using Microsoft.Xna.Framework;
using Terraria;
using Terraria.ID;
using Terraria.ModLoader;


namespace DrewsSword.Items
{
	public class DrewSword : ModItem
	{
		// The Display Name and Tooltip of this item can be edited in the Localization/en-US_Mods.DrewsSword.hjson file.

		public override void SetDefaults()
		{
			Item.damage = 100;
			Item.DamageType = DamageClass.Melee;
			Item.width = 40;
			Item.height = 40;
			Item.useTime = 10;
			Item.useAnimation = 10;
			Item.useStyle = 1;
			Item.knockBack = 6;
			Item.value = 10000;
			Item.rare = 2;
			Item.UseSound = SoundID.Item1;
			Item.autoReuse = true;
		}

		public override void AddRecipes()
		{
			Recipe recipe = CreateRecipe();
			recipe.AddIngredient(ItemID.DirtBlock, 10);
			recipe.AddTile(TileID.WorkBenches);
			recipe.Register();
		}

		public override void MeleeEffects(Player player, Rectangle hitbox)
		{
			if (Main.rand.NextBool(3))
			{
				// Emit dusts when the sword is swung
				Dust.NewDust(new Vector2(hitbox.X, hitbox.Y), hitbox.Width, hitbox.Height, 74);
			}
		}

		public override void OnHitNPC(Player player, NPC target, NPC.HitInfo hit, int damageDone)
		{
			// Inflict the OnFire debuff for 1 second onto any NPC/Monster that this hits.
			// 60 frames = 1 second
			target.AddBuff(BuffID.OnFire, 60);
		}
	}
}

A few useful links for the above
https://github.com/tModLoader/tModLoader/wiki/Basic-tModLoader-Modding-Guide
https://terraria.fandom.com/wiki/Dust_IDs
https://github.com/tModLoader/tModLoader/blob/1.4.4/ExampleMod/Content/Items/Weapons/ExampleSword.cs