Mateus is another Esper that is fought during a regular playthrough of the game. The party will encounter him in the Stilshrine of Miriam.
Mateus is fought in the Hall of Worth at the end of the Stilshrine of Miriam.
Level: 50
HP: 209,060
Steal: 
Leo Gem (55%), 
Hi-Ether (10%), High Arcana (3%)
Mateus will begin the battle by casting Reflect on itself and by summoning five Ice Azer enemies to aide it in battle. Start off by defeating each of the Ice Azer enemies as they will spam your party with Sleep spells and 
Blizzard Magick.
Use 
Protect, Shell and 
Haste on your party members if you have enough MP. Protect will reduce the amount of damage done by Mateus’ regular attacks, Shell will reduce the damage done by the Ice Azers until you have defeated all of them and Haste will greatly increase the amount of damage done by your party members.
Mateus is not weak to any negative status effects (except for Oil which will not help you in this fight). The Ice Azers are susceptible to Thunder and Thundara Magick, but you risk hitting Mateus with Thundara spells which will then be reflected back at the caster.
You can use Quickenings or summon Belias to do a fair bit of damage to Mateus and the Ice Azers if you are running into problems. Use 
Decoy and an 
Ice Shield to have the boss and the Azers focus on your strongest team member. Mateus will do more damage once its HP gets low.
A video of the battle in the Zodiac Age version is included below:
Congratulations – you now have Mateus as an Esper which you can use in battle!
Hashmal has two Ice-type attacks. His regular attack is very similar to Blizzard and causes Ice damage to one foe. His ultimate attack, Frostwave, deals Ice-type damage to all foes in range.
Unlocking Mateus on the License Boards of certain jobs will unlock additional License Boards:
Caldera, Volcano)Curaga, Regen), White Magick 7 (Cleanse, Esuna)
Gil TossThe optimal selection for Mateus is to give it to your Knight to make sure that it gets all of the White Magick spells available. The only other option is to give it to your Time Battlemage for the extra HP.
