The Tomasi Legions relied on Summoners and conjuration Magic to march across the Maru Sea. The
The Tomasi Empire's best Summoner-Legionnaire bore the shields of the Empire. With these shields, the Tomasi Legion's eidolons- summoned creatures for lack of a better word- acted with discipline and combined might. The shield also kept the Eidolon under control, even when the Legionnaire had died or lost control for other reasons. These shields were the foremost tool that made the Legions strong.
But the greatest generals of the Legions, the Maximi, wielded artifacts of considerable power. The Legion-Gems magnified their Eidolon's powers. Using a mix of Magus and Witch techniques, each Gem changed the Maximi and their Legion's Eidolons in unique ways. Legions were named often based on their Maximi's Gem. The Wind's Legion, the Legion of Wolves, the Shark-God's Legion, etc.
Nowadays, not much remains of the Legions of the Tomasi Empire. The Legion-Gems for each of the thirty-seven Tomasi Legions have been lost- only the Gems for six remain, all in the control of the Ithic Military. Summoners of any stripe could benefit greatly from the use of any of these gems, making them a target for treasure hunters of all kinds.
Another remnant of the Tomasi Legions, however, are the Vagabonds. These are eidolons who have gone feral. Wild-creatures, they became trapped on Orphos after the deaths of their Legionnaire. Ancient Tomasi magicks have allowed them to remain. Most carry the shields of their fallen masters. Some grow weaker from the centuries, but some also grew stronger. Freed, they found corners in Ith and the rest of the Maru Sea to live in.