From Final Fantasy Wiki

Lv? Death is a Blue Magic obtainable for Quistis Trepe in Final Fantasy VIII.

It can be learned from the item Curse Spike, which can be found or win from Malboro, Forbidden, Imp, Creeps, Grand Mantis, and Tri-Face, and as a Card Modification of the Tri-Face card.

It casts Death on all enemies based on the Crisis level on her HP.

• Crisis Lv.1 - Lv.4 Death
• Crisis Lv.2 - Lv.3 Death
• Crisis Lv.3 - Lv.2 Death
• Crisis Lv.4 - Lv.1 Death