Dazzling Heart

The Dazzling Heart is a permanent health booster that will grow on Pearlstone Blocks, Pearlsand and Pink Ice Blocks in Underground Hallow biome after the world enters Hardmode. A Dazzling Heart will emit a glow similar to Crystal Shards, making them easy to spot while underground. When used, it permanently increases the player's health capacity by 5, adding 2 crystal hearts to the player's health bar, while also restoring 5 health. upon use, the Dazzling Heart will be consumed. Up to 10 Dazzling Hearts can be used, increasing health capacity to 450 (10 hearts).

Additional Dazzling Hearts can no longer be used at that point, and attempting to do so will not consume the item. After the 450 health maximum is reached from consuming Life Crystals, Blazing Hearts, and Dazzling Hearts, Life Fruits can then be used to increase health capacity further, to a maximum of 500 (10 Life Fruits).

Trivia

 * This item, as well as the new heart system as a whole, was originally suggested by Snickerbobble on Terraria Community Forums.
 * Despite not appearing on the achievements screen in-game, using this will give you the "Get A Life" Achievement.
 * Even though the item forbids the use of Life Fruit at 400 HP, the Life Fruit can still be used via the Autopause glitch, making the usage of the Dazzling Heart optional.