Nerf

A nerf is a card change that causes a card to become less effective or less powerful. The opposite of a nerf is a buff (not to be confused with the identical term for an enchantment).

In Hearthstone, nerfs are often called for by players when a card or deck in a particular meta is deemed to be too powerful, non-interactive, or simply too frustrating to play against. In addition, nerfs can also be design-related, called for by the developers when it is necessary to keep in line with a design goal in mind while simultaneously avoiding potential problems with future cards that may be printed.

The degree to which the power of a card should be nerfed can prove difficult to determine, and it requires some foresight into future cards. A card may be too strong in a particular meta, and if it is nerfed, it might still see some play; however, in future metas, the nerf may have been too drastic and the card may be too weak to ever see any play, unless new cards are printed to synergize with the nerfed card again. New cards and developments cause cards to become either effective or ineffective, in different and unforeseen ways, depending on the meta, and these issues should reflect the degree of power of a nerf.

In Hearthstone, the developers have a strong stance of nerfing cards only when absolutely necessary, but have done so on numerous occasions. Most nerfs are fairly straightforward mathematical reductions in power, such as increasing a card's mana cost by one, or decreasing a minion's health by one. Nerfs currently comprise the majority of all Hearthstone card changes; buffs to cards are rarely seen as there is little incentive to do so, but reversions of nerfs have been touched upon in discussions, and these may occur in the future (for cards such as Molten Giant).

When a nerf happens, players are allowed to disenchant nerfed cards for their full crafting cost, for a short period after the nerf occurs. See Card_changes.

For more information on nerfs and card changes, as well as a list of all card changes to date, see Card change.