Ifnir Deadlands

{T}: Add {C}.
{T}, Pay 1 life: Add {B}.
{2}{B}{B}, {T}, Sacrifice a Desert: Put two -1/-1 counters on target creature an opponent controls. Activate only as a sorcery.

Amonkhet Remastered

{T}: Add {C}.
{T}, Pay 1 life: Add {B}.
{2}{B}{B}, {T}, Sacrifice a Desert: Put two -1/-1 counters on target creature an opponent controls. Activate this ability only any time you could cast a sorcery.

Hour of Devastation

{T}: Add {C} to your mana pool.
{T}, Pay 1 life: Add {B} to your mana pool.
{2}{B}{B}, {T}, Sacrifice a Desert: Put two -1/-1 counters on target creature an opponent controls. Activate this ability only any time you could cast a sorcery.

Desert is a land subtype with no special meaning. It doesn’t grant the land an intrinsic mana ability. Other cards may care about which lands are Deserts.

If a Desert has an ability with a cost of “Sacrifice a Desert,” you can sacrifice that Desert to pay the cost for its own ability.