Coupled with any of those sources, the Rain of Starless Skies lets your build spam Core Skills against Elites and bosses with little issue.

Ice builds can pair this with the Frigid Breeze and Avalanche passives, fire builds can use the Fiery Surge passive and the Engulfing Flames Aspect, and lightning builds can use Crackling Energy to restore mana. Similar to Mother's Embrace, this ring alone won't be enough to fix the Sorcerer's mana sustain issues, but it can be a major help when paired with another mana source. This bonus adds up quickly and allows you to spam skills like Chain Lightning far more often. This ring reduces the mana cost of your Core Skills for each Core Skill you've recently cast, granting up to a 40% cost reduction. The Harlequin Crest Shako is well worth searching for, as it’s one of the best unique helms in the game. If your Sorcerer build focuses on spamming a Core Skill, Rain of Starless Skies is a Unique you'll want to consider using. Rain of Starless Skies: Each consecutive Core Skill cast reduces the resource cost of your next Core Skill by, stacking up to 40%.

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