King's Crown

The King's Crown adds two points to each of Intelligence and Faith. Gather all four crowns and receive the King's Blessing from Vendrick. While equipping any of the four crowns, the blessing prevents your character from being hollow due to death or curse. A blessed crown has the same anti-curse effect as the Hollow Skin, the effect lasting only during the current playthrough. Moving on to the next NG cycle would remove the blessing and you must obtain Vendrick's blessing again for the same anti-curse effect.

Vendrick

SL1 Vendrick, Dark Souls 2: SotFS

This boss is a tank, despite being naked and covered with nothing but a loincloth. Have Soul of a Giant x 5 in your inventory as a means of lowering Vendrick's defense. Consume a Brightbug before triggering the fight. Since Vendrick can one-shot you, you might as well equip the Red Tearstone Ring and decrease your HP low enough to trigger its effect. Position your character behind Vendrick's left leg and strafe to your right whenever he swings his sword. Have at least 15 Adaptability to allow you to roll through the boss' attacks.

Location of King's Crown, Dark Souls 2: SotFS

Defeat Vendrick and revisit Shrine of Amana. Start from the Crumbled Ruins bonfire and proceed to a stone bridge that was previously guarded by a Dragonrider. Cross the stone bridge and be in human form to open a door. The King's Crown is found inside a chest. Collect the King's Crown. Next, return to the arena where you fought Vendrick, enter the Memory of the King, exhaust Vendrick's dialogue, and you would receive Vendrick's blessing.