I couldn't finish 'em. Looks like this's gonna get complicated.
The battle is fought in five parts. The first four parts have 1,600 HP each, and although there is no visual transition between them, they each have minor differences in their stats. After defeating the fourth part, the monster fades like a defeated enemy and is revived.
Archeoaevis will sometimes use Wall Change to change its weakness. Its most powerful attack in his first form is Blaze that does around 250 damage to each party member, and inflicts Sap. Archeoaevis's only other random attack is Thunder, a level one spell that deals negligible damage, though it hits the whole party.
Once defeated, Archeoaevis reappears and casts Maelstrom, its strongest attack, reducing everyone to HP Critical status. After it reappears, it becomes immune to most forms of magic, but spells like 1000 Needles and Goblin Punch are still effective.
Archeoaevis might confuse an ally.
One party member should be constantly scanning it to reveal Archeoaevis's current weakness.
Throwing Shurikens with the Throw command is useful. Using Cura is essential. It is advised to use Cura on all party members, even if not every member requires healing. Death Claw also seems to work on Archeoaevis's first form.
Archeoaevis can be easily killed by the Blue Magic 1000 Needles. It takes 8–9 turns to kill him, but this will be easier with the party of four Blue Mages, or any job with the Blue Magic command equipped.
Other appearances Edit
The creature's name comes from the Greek suffix archeo- meaning "ancient" and the Latin word avis meaning "bird".