- “Ancient Thamasan orb enshrining a wondrous power. Changes the Magic command to Dualcast.”
- —Description, Final Fantasy VI.
The relic Soul of Thamasa (called Gem Box in the SNES translation) grants the wielder the ability of Dualcast, but disables the use of summoning espers. It originally could only be acquired atop the Cultists' Tower, but in the Advance and smartphone remakes, additional others can be stolen from Glutturn. Thamasa is a town founded by disgraced mages and populated by their descendants, and one of the only places left in the world where magic is still practiced; the item's name alludes to the town.
The Soul of Thamasa, mistranslated as Samantha Soul, is a Guardian Force ability item that teaches the SumMag+40% ability to a Guardian Force. Three can be acquired through refining Quistis's card, while others can be stolen from Adel, or by refining 50 Energy Crystals into a Samantha Soul. 20 Samantha Souls can be refined into 1 Elem-Atk or 60 Triples.
The Soul of Thamasa is an accessory that doubles MP consumption of the wielder for all spells, but strengthens the effects of said spells. They can be bribed from an Oversoul Detonator and Volcano, stolen from Volcano, or won from Ixion. One can also be received as a reward for completing the monkey sidequest in Zanarkand in Chapter 2.
- “A coalescence of goodwill found buried deep inside a corrupt and evil heart. It glistens like an uncut gemstone.”
Soul of Thamasa is a head-type accessory. It increases the number of attacks before the combo finale by 1 and reduces maximum HP by 66%. Re-obtaining the Soul of Thamasa ranks it up to Soul of Thamasa+ and decreases the maximum HP reduction to 50%. The player can find it in the Wildlands, in the the northern part of the City of Ruins. The player will need to glide with the Angel of Valhalla and need 6 EP to open the treasure sphere.
The Soul of Thamasa is an accessory that raises Magic Attack by 10% and Intellect by +5 points. It is acquired as treasure earlier in the game, and is later available at the item shops in Urbeth.
Soul of Thamasa is an accessory that increases the wearer's Intelligence by 20.
The Soul of Thamasa is an accessory that raises magic damage by 20%, Wall Rush Bravery damage by 10%, and Chase Bravery damage by 10%. It can be obtained by trading 2,000 gil, a Star Earring, a Rocket Engine, and five Tomes of the Farplane. In her EX Mode, Terra's "Chainspell" ability is described as "embracing the spirit of a magus", referring to the Soul of Thamasa from Final Fantasy VI that gives the Dualcast skill.
The Soul of Thamasa increases magic damage by 3%, Wall Rush Bravery damage by 40%, and Chase Bravery damage by 7%. It can be traded for an Earring, a Jet Engine, a Tome of the Farplane, and 3,500 gil.