Old Knight's Flask

 is an active item.

Effects

 * Heals the player for one heart upon use.
 * Starts with 2 charges, and refills to 2 charges at the start of each floor.

Synergies

 * If the player also has Sunlight Javelin, when Sunlight Javelin kills an enemy, it will spawn a circular zone that ignites all enemies within it.
 * If the player has Crestfaller, reloading it will fire a glass bottle that will stun enemies it hits. Reloading Crestfaller while standing on a liquid replenishes the ammo missing in the current magazine, similar to Gungine.
 * If the player has Gun Soul, a bonfire spawns in every shop, elevator, and Crest room. If the player dies, they will respawn at the last bonfire they activated instead of at the start of the floor. Additionally, dodge roll recovery time is reduced.

Trivia

 * This item is a reference to the Estus Flask from Dark Souls.
 * The and  synergies are references to Solaire of Astora from Dark Souls and his well-known catchphrase, "Praise the Sun!"
 * This item's synergy with Crestfaller is a reference to the NPC Crestfallen Warrior in Dark Souls.
 * Based on the fact that Old Knight's Helm and Old Knight's Shield belonged to Ser Manuel, this likely also belonged to him.