If you want the best sword enchantments in Minecraft, focus on a core core set that covers damage, durability, loot, and versatility, then adapt for PvP or specific mobs as needed. Direct answer

• Core best enchantments for a general-purpose sword: Sharpness V, Unbreaking III, Mending, Looting III (optional for farming drops), and Fire Aspect II or Sweeping Edge III (to add area damage and crowd control). For undead or specific mobs, consider Smite V or Bane of Arthropods V in place of Sharpness V as needed. Knockback II can help in PvP or to manage mobs, but use on a case-by-case basis.

Context and reasoning

• Sharpness increases overall damage across all targets, making it the default choice for a primary combat sword. Unbreaking III extends the sword’s lifetime, reducing repair needs. Mending uses XP to repair durability, effectively preventing weapon loss in longer play sessions. Looting III increases drops from mobs, which is especially valuable for farming rare drops (like Skeleton or Wither Skeleton skulls) or farming items from mobs that drop more with Looting.
• Fire Aspect II adds burning damage, which compounds with base damage and makes mobs easier to kill, while Sweeping Edge III improves sweeping attacks, increasing efficiency against groups of enemies.
• Smite V and Bane of Arthropods V are mutually exclusive with Sharpness V (you can’t have both on the same sword in standard rules). Choose Smite V if your focus is undead (zombies, skeletons, ghasts? actually ghasts are not undead) or Bane of Arthropods V for spiders and related mobs. For a broad, all-purpose sword, Sharpness V is typically superior.
• PvP considerations: Sharpness V, Fire Aspect II, and Knockback II are common combos to maximize damage and control. Mending remains valuable in PvP to keep the weapon from breaking during long fights. If you prefer to push opponents away, Knockback II is useful; if you want to maximize damage against players quickly, prioritize Sharpness V and Fire Aspect II.

Notes

• Availability depends on your Minecraft version (Java vs Bedrock) and whether you are playing in survival or creative. In general, the upgraded enchantment levels (V for Sharpness, Looting, Fire Aspect; III for Unbreaking, Mending) are the standard cap in most non-creative modes.
• If time or resources permit, you can wield two swords: one with Sharpness V for general use and another with Smite V or Bane of Arthropods V for farming specific mobs—though this requires swapping weapons during play.

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