Demon Hearts are a very useful resource in Terraria. They can be quite difficult to get, however, and are exclusive to a particular mode.

This shouldn’t put you off obtaining them, as their ability to help with late-game makes them worth the challenge.

Expert mode is a difficult task in itself, so knowing how to use Demon Hearts in Terraria is essential. 

How to Get Demon Hearts

Demon Hearts are exclusive to expert mode. This means that your world must be in expert mode to be able to obtain them and use them. Additionally, their effects will be negated in worlds that aren’t at least expert difficulty.

Expert mode is a gamemode in Terraria that is selected at world creation. Expert mode worlds have increased difficulty, with enemies dealing more damage, having new attacks, more health, and sometimes inflicting debuffs to you. Additionally, the difficulty of bosses is affected by the same factors.

On the other hand, the quality and quantity of loot is greatly increased, allowing you to obtain rare loot more easily, as well as more coins.

Due to Demon Hearts only being available in expert mode, they are more difficult to obtain than items that are found in all modes.

Demon Hearts are acquired from Treasure Bags dropped after defeating the Wall of Flesh in expert mode. The Wall of Flesh is the final pre-hardmode boss and – upon defeating it – you will enter hardmode. 

Entering hardmode is a pivotal moment in the game, as it increases the difficulty of the game by a significant amount while also unlocking a vast array of new content. 

The Wall of Flesh can be summoned by throwing a Guide voodoo doll (a guaranteed drop from the rare Voodoo Demon enemy) into lava, while there is a Guide present in your world.

Prior to fighting the Wall of Flesh, sufficient preparation is crucial. Arguably the most important preparatory factor is building a flat platform along the underworld. This will ensure there are no obstructions when fighting the challenging, final non-hardmode boss and you will therefore be able to focus entirely on dishing out damage and keeping yourself healthy.

It’s also advised to place campfires and heart lanterns along your platform to increase health regeneration as well as stars in bottles to increase mana regeneration (if you use magic). Bast statues give a defense buff to nearby players when placed so it’s wise to utilize this too. 

Another key factor in fighting the Wall of Flesh, particularly in expert mode, is ensuring you are carrying approximately a stack of the highest-tier healing potion available to you. Relying solely upon health regeneration isn’t a good idea, and having burst healing readily available is hugely advantageous. 

How to Use Demon Hearts

Demon Hearts are very easy to use – fully utilizing their benefits, however, can be a more challenging task. To use a Demon Heart, simply put it in your hotbar, select it and consume it – the same as consuming a potion. 

Once you have used the Demon Heart, you will be granted an extra accessory slot. Demon Hearts can only be used up to once per character. It is important to note that this extra accessory slot will only be available in expert and master mode worlds and – upon joining a world that is not at least expert mode – the additional accessory will be placed into your inventory.

Additionally, in master mode, the default number of accessory slots in 6, meaning that – with a Demon Heart – you can get up to 7 accessory slots on a master mode world.

If you defeat the Wall of Flesh in expert mode, after having already consumed a Demon Heart, you will not receive another one from the Treasure Bag.

Utilizing this extra accessory slot is mainly dependent on the class setup you are playing. For example, if you are playing a mana-hungry, damage-heavy class like mage, you wouldn’t necessarily want the same items as a tanky, predominantly defensive class such as melee. 

Conclusion

Demon Hearts are an incredibly useful accessory to help you with the challenge of hardmode in expert and master mode worlds.

They are simple to use but difficult to get, however the challenge is certainly worth it – given the major benefit they give in expert/master mode. It’s recommended to fully utilize this benefit to assist you in progressing through the game in at least expert mode.