Graceling, by Kristin Cashore

A world where some people are "graced" with special powers (otherwise your usual pseudo-European nobility world) and whose lives are irrevocably complicated because of this.

Shadow and Bone by Leigh Bardugo

An alternate Russia where those who can manipulate the elements in a war-torn land live in luxury while others starve. Can the childhood bonds between two orphans save them?

Daughter of Smoke and Bone, by Laini Taylor

An art student in Prague has a secret life collecting teeth for a demon-like creature to whom she owes her life. Loyalty, love, and self-identity are all tested when she encounters an angel-like creature near the shuttered entrance to the demon's lair.

All three of these fantasies feature delicately and lovingly crafted alternate worlds that completely transported me away. (Daughter of Smoke and Bone and Graceling in particular.) But what sets them apart from other fantasies out there, besides the world-building, is how much the characters in these stories invaded my heart.

Be careful, they'll take up residence inside you and challenge your peace of mind.