I couldn't finish 'em. Looks like this's gonna get complicated.
Template:FFIV:TAY Enemies Deathmask is an enemy from Final Fantasy IV: The After Years.
The Deathmask is more or less the same enemy as in Final Fantasy IV. It will start off casting Reflect on itself, and then all of your party members. Then it will start casting Holy, Flare, and Bio on itself and every now and again casting Curaga on your entire party to heal itself. If it comes with a Full Body, it will cast Reflect on its companion in addition to itself, and later on cast Haste on your party, ostensibly to Reflect it onto its own side.
The best way to handle a Deathmask is to cast Black Magic on yourself due to the Reflect spell, or use Rydia's Summon ability. For healing, you should consider using X-Potions to get around the Reflect status. If Edward Chris von Muir is in your party, then his Salve ability should be excellent in the most critical of situations.