Plague

Plague is a type of creature similar to the Ahriman or Floateye. It is encountered in Final Fantasy IV in the Lunar Subterrane and in the Final Fantasy VI GBA remake.

[[Final Fantasy IV]
Plague is infamous for casting Doom on the whole party, then casting Haste on the whole party. The ideal strategy against this is to get Kain to use the Jump command long before Doom is cast. If this is not possible, the player can kill then revive an ally removing their doom counter. This throws off Plague's strategy and it will attempt to cast Doom and Haste all over again. Plague also does this around 11th turn (since the Doom spell lasts for 10 seconds). The beginner's strategy involves killing Plague with Holy spells and projectiles before the entire party falls.

The Holy Lance is the reward for killing Plague.

[Final Fantasy VI]
Plague appears in the Dragon's Den as a sub-boss. Similar to the Final Fantasy IV incarnation, this monster also casts Condemned on the whole party.