Soul Shards can drop from any type of content and game mode, be it Bounties, Nephalem (Standard) Rifts, or Greater Rifts. Soul Shards however have a higher chance to drop from Bosses, including an unlisted mechanic outlined below. You can get specific Soul Shards from specific Act bosses in Adventure Mode as early as level 1, making them a target-able bonus from the very beginning of character progression and a massive boon during leveling. The tactic works all the way to level 70 and beyond, making it a viable way to farm the Soul Shards whenever you need a new roll. Act I: Essence of Anguish (Weapon shard) — ~25% drop chance from any act boss Act II: Dregs of Lies (Weapon shard) — ~25% drop chance from any act boss excluding Vidian Act III: Stain of Sin (Weapon shard) and Fragment of Destruction (Helm shard) — ~12.5% chance to drop both (or none) from any act boss Act IV: Remnant of Pain (Weapon shard) and Sliver of Terror (Helm shard) — ~12.5% chance to drop both (or none) from any act boss Act V: Shard of Hatred (Helm shard) — ~50% drop chance from any act boss While they are all powerful in their own right, not all of these Shards will be at their full potential outside of complete endgame builds. Some of them will fare much better than others during the leveling process, and the actual best thing to do with your first Soul Shards is to salvage them for a chance at acquiring level 70 standard gems. It is recommended that you farm the following Soul Shards for leveling: Any class — Important at Level 1: Kill Zoltun Kulle in Act II for a Soul Shard to salvage. This will net you 3 random gems of Marquise or Imperial quality, with a minor chance to give 1 Flawless Royal gem instead. The chance to get Rubies of any of these tiers of quality will be so influential to your leveling that doing 5-10 runs of Zoltun Kulle near the start of your leveling process to guarantee the Ruby drops is not unreasonable. Any class: Kill Rakanoth in Act IV for Sliver of Terror. Rakanoth is easy to reach, and this Shard will fit almost any build as it empowers you for every cooldown you add to your skill bar. The alternative Shard you can get from Act IV, Remnant of Pain, can also be decent if you have access to a hard crowd control skill from early on. Cooldown-dependent classes (Barbarian, Crusader, Wizard): Kill Azmodan for Fragment of Destruction, whose Messerschmidt's Reaver-like proc can help you get impactful cooldowns available (Wrath of the Berserker, Akarat's Champion...) much faster. Pet-based classes (Necromancer, Witch Doctor, Monk with an early gamble of The Crudest Boots): Kill Zoltun Kulle or Maghda in Act II for Dregs of Lies. If you level via Massacre bonuses: Consider killing Malthael (despite the slow fight) to get Shard of Hatred, which scales your damage the bigger your pull is.