Legio Tertiolus is a miniature version of Legio Tertius that can be unlocked as a pet from a Corrupted Ascension signet III, which is obtained as a drop from killing Legio Tertius. The chances of obtaining the item increases with the number of kills recorded in the beasts tab (explanation of drop mechanics). After the item is used, Legio Tertiolus can be summoned from the pets tab in the hero interface.
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